[cheerful upbeat music] ♪ ♪ HEY, MY NAME IS MR. R., AND I CAME TO SAY ♪ ♪ I LOVE CLASSROOM CONNECTION IN A MAJOR WAY ♪ WHAT'S UP, MY SUPER LEARNERS?

AND WELCOME TO ANOTHER DAY TO DO SOME SUPER LEARNING.

HOW'S EVERYBODY DOING?

LET'S SEE THEM THUMBS-UP.

[chuckles] THERE IT IS.

I LIKE TO SEE THAT.

NOW, WHAT'S THE BEST THING YOU CAN DO WHILE INSIDE?

LEARN SOMETHING COOL WITH THAT SUPER LEARNER MIND.

YO, CHECK THIS OUT.

♪ HI!

WE ARE THE SUPER TWIN TEACHERS, GRACE AND CLAUDIA.

[fanfare plays] THIS MATH LESSON WILL BE HELD IN SPANISH AND WILL HAVE ENGLISH CAPTIONS.

WE ARE HAPPY THAT YOU CAN JOIN US TODAY.

HI, SUPER LEARNERS.

WE ARE CLAUDIA AND GRACE, THE SUPER TWIN TEACHERS!

[fanfare plays] WE ARE SO HAPPY THAT YOU ARE HERE.

ARE YOU READY FOR ANOTHER MATH ADVENTURE TODAY?

LET'S GO, WITH OUR MATH POWER WARM-UPS.

AND THEN, OUR MISSION FOR TODAY IS TO COMPARE AND ANALYZE GEOMETRIC SHAPES WHEN DRAWING AND BUILDING THEM.

SO, LET'S START.

[speaking Spanish] HI, SUPER LEARNERS.

WE'RE THE POWERFUL TWINS, CLAUDIA AND GRACE.

[fanfare plays] WE'RE VERY HAPPY THAT YOU'RE HERE.

ARE YOU READY FOR ANOTHER MATH ADVENTURE TODAY?

THEN, LET'S GET STARTED.

SUPER LEARNERS, TODAY'S MISSION IS TO COMPARE AND ANALYZE GEOMETRIC SHAPES BY DRAWING THEM AND BUILDING THEM.

BUT, TO START, WE'LL SING OUR SONG.

READY?

YES.

[both] ♪ HELLO, SUPER LEARNERS HOW ARE YOU?

♪ ♪ HELLO, SUPER LEARNERS HOW ARE YOU?

♪ ♪ WE'RE VERY HAPPY THAT YOU ARE HERE ♪ ♪ AND WE HOPE YOU FEEL THE SAME ♪ ♪ HELLO, SUPER LEARNERS HOW ARE YOU?

♪ WE FEEL GREAT TODAY, AND WE HOPE YOU DO TOO.

LET'S START WITH OUR MATH POWER WARM-UPS, SINGING AND COUNTING UP TO 20.

ARE WE READY?

YES?

HERE WE GO!

VERY GOOD, SUPER LEARNERS.

ARE YOU READY, GRACE?

YES, OF COURSE.

LET'S GO.

♪ LET'S COUNT, LET'S COUNT ♪ ♪ SUPER LEARNERS, LET'S COUNT ♪ ♪ 1, 2, 3 WE MOVE OUR FEET ♪ ♪ 4, 5, 6 OUR HANDS TOO ♪ ♪ 7, 8, 9 WE MOVE OUR BODIES ♪ ♪ AND, 10 WE LISTEN CAREFULLY ♪ ♪ 11, 12, 13 WE COUNT LOUDLY ♪ ♪ 14, 15, 16 WE JUMP ALL AT ONCE ♪ ♪ 17, 18, 19 MY HEAD MOVES AROUND ♪ ♪ AND, 20 WE COUNT ALL OVER AGAIN ♪ NOW, IT'S TIME TO REVIEW OUR COLORS IN ENGLISH AND IN SPANISH.

WILL YOU JOIN US?

GREAT.

WHAT COLOR IS THIS?

YES, NEGRO.

BLACK.

AND THIS ONE?

YES, NARANJA.

ORANGE.

AND THIS ONE?

YES, CAFÉ.

BROWN.

LOOK FOR THESE COLORS IN THE WORLD TODAY.

AND OUR LAST WARM-UP IS TO REVIEW THE SHAPES IN ENGLISH AND IN SPANISH.

WHAT SHAPE IS THIS?

YES, RECTÁNGULO.

RECTANGLE.

AND THIS ONE?

YES, ROMBO.

RHOMBUS.

AND THIS ONE?

YES, TRAPEZOIDE.

TRAPEZOID.

LOOK FOR THESE SHAPES IN THE WORLD TODAY.

GREAT, SUPER LEARNERS!

GREAT.

WE HOPE YOU'RE READY, BECAUSE IT'S TIME FOR... [both] OUR MATH MISSION OF THE DAY!

GREAT, SUPER LEARNERS.

LET'S CHECK WITH OUR FRIENDS TO FIND OUT THE MISSION OF THE DAY.

MMM... SUPER LEARNERS, TODAY'S MISSION IS TO COMPARE AND ANALYZE GEOMETRIC SHAPES BY DRAWING THEM AND BUILDING THEM.

WOW, I'M SO EXCITED FOR THIS MISSION.

SUPER LEARNERS, ARE YOU READY?

COME ON!

SO, LET'S START BY LOOKING AT WHAT WE HAVE HERE.

WHAT DO YOU SEE, SUPER LEARNERS?

YES, VERY GOOD.

HERE WE HAVE CLAY AND PIPE CLEANERS.

WHAT CAN WE MAKE WITH ALL THIS?

LET'S THINK.

OF COURSE.

WE CAN MAKE SHAPES.

SO, WE'LL GET OUT SOME CARDS, AND ON EACH ONE IS A SHAPE.

AND WE'RE GOING TO MAKE IT WITH ALL THESE MATERIALS.

LET'S START WITH THE FIRST CARD.

WHAT IS THIS SHAPE CALLED?

RIGHT, TRIÁNGULO (TRIANGLE).

AND HOW CAN WE MAKE IT?

HOW MANY PIPE CLEANERS WILL WE NEED?

I'M LISTENING.

YOU SAID... 3?

VERY GOOD.

BUT SOMETHING IS MISSING.

RIGHT!

3 VERTICES.

LET'S COUNT.

HERE ARE THE VERTICES.

LET'S MAKE IT.

A PIPE CLEANER, ONE SIDE, A VERTEX, ANOTHER SIDE, A VERTEX, ANOTHER SIDE... HELP ME.

UH-OH... AND WE DID IT!

THERE IS THE TRIANGLE WITH ITS VERTICES.

VERY GOOD, SUPER LEARNERS.

VERY GOOD.

NOW, LET'S SEE THIS OTHER CARD.

WHAT IS THIS SHAPE CALLED?

VERY GOOD.

EL CUADRADO (THE SQUARE).

AND HOW MANY PIPE CLEANERS DO WE NEED TO BUILD IT?

YES!

4 PIPE CLEANERS.

AND WHAT ELSE?

4 VERTICES!

4 LITTLE BALLS.

LET'S MAKE IT.

ONE SIDE, ANOTHER SIDE, ANOTHER SIDE, AND ANOTHER SIDE.

LET'S PUT ON THE VERTICES.

HERE'S A VERTEX, HERE'S ANOTHER VERTEX, ANOTHER HERE, AND ANOTHER HERE.

DID WE DO IT?

DO THE 2 LOOK ALIKE?

VERY GOOD.

WE DID IT.

A SQUARE.

NOW, WE'LL CONTINUE.

AND OUR NEXT SHAPE IS CALLED... RECTÁNGULO (RECTANGLE), YES.

VERY GOOD, SUPER LEARNERS.

WHAT DO WE NEED, TO MAKE THIS RECTANGLE?

HMM?

YES.

VERY GOOD.

2 LONG PIPE CLEANERS AND 2 SHORT PIPE CLEANERS.

WHAT ELSE WILL WE NEED?

VERY GOOD.

4 SPHERES.

...WHICH ARE THE VERTICES.

LET'S START.

1 LONG PIPE CLEANER, WHICH IS 1 SIDE, A VERTEX, A SHORT SIDE, ANOTHER VERTEX, A LONG SIDE, ANOTHER VERTEX, A SHORT SIDE, AND ANOTHER VERTEX.

LET'S LOOK AT THE SHAPE.

VERY GOOD, SUPER LEARNERS.

WE DID IT.

VERY GOOD.

AND WHAT IS OUR LAST CARD?

WE HAVE A...

YES!

UN CÍRCULO (A CIRCLE).

AND WHAT CAN WE USE-- WHAT DO WE NEED?

RIGHT, WE CAN USE PIPE CLEANERS, OR CLAY.

LET'S SEE.

HOW CAN WE DO IT, SUPER LEARNERS?

JOIN ME.

LET'S SEE, LET'S SEE, LET'S SEE, LET'S SEE... [gasps] WOW!

WE DID IT!

HERE IT IS.

THANK YOU, SUPER LEARNERS, FOR HELPING US TO COMPLETE THE FIRST PART OF THE MISSION.

MM-HMM.

WE WERE ABLE TO MAKE ALL THESE GEOMETRIC SHAPES.

IT'S TIME TO MOVE OUR BODIES, USING MATH.

OKAY, SUPER LEARNERS?

SO, LET'S BEGIN.

SUPER LEARNERS, ARE YOU READY?

HERE I HAVE A RING.

YOU AND GRACE ARE GOING TO CLAP.

WHEN I RAISE IT, YOU STOP.

ARE WE READY?

YES, CLAUDIA.

HOW FUN!

HERE WE GO.

CLAP, GRACE.

[clapping] [silence] VERY GOOD!

WE DID IT!

NOW WE FEEL GREAT AND REENERGIZED.

YES, SUPER LEARNERS.

WHAT COMES NOW?

THE SECOND PART OF OUR MISSION.

WE FEEL REENERGIZED.

NOW, SUPER LEARNERS, LET'S CONTINUE.

THE SECOND PART OF OUR MISSION IS TO HELP OUR FRIEND THE BUTTERFLY GET TO ITS FLOWER.

TO GET TO THE FLOWER, WE HAVE TO IDENTIFY THE GEOMETRIC SHAPES THAT WE FIND ALONG THE WAY AND FINISH THEM.

HOW EXCITING.

READY?

YES!

LET'S BEGIN.

OH!

WE FOUND AN OBSTACLE.

WHAT CAN IT BE?

LET'S FINISH IT.

A STRAIGHT LINE, A VERTEX, A STRAIGHT LINE, A VERTEX, A STRAIGHT LINE, A VERTEX... SUPER LEARNERS, WHAT DID WE MAKE?

CORRECT, A TRIANGLE!

LET'S FOLLOW THE PATH.

AND WE'VE FOUND ANOTHER OBSTACLE.

UH-OH!

WHAT CAN IT BE?

LET'S COMPLETE IT TO KNOW WHAT IT IS.

A SHORT, STRAIGHT LINE, A VERTEX, ANOTHER STRAIGHT LINE, BUT LONG, A VERTEX, ANOTHER SHORT STRAIGHT LINE, A VERTEX, AND ANOTHER LONG STRAIGHT LINE, AND A VERTEX.

SUPER LEARNERS, WE'VE MADE A...

YES, A RECTANGLE.

CLAUDIA, DO YOU WANT TO HELP OUR FRIEND THE BUTTERFLY TOO?

OF COURSE.

AND I ALSO NEED THE HELP OF OUR SUPER LEARNERS.

COME ON, LET'S FOLLOW THE PATH.

MMM... WHAT DID WE FIND?

ANOTHER OBSTACLE.

WHAT CAN IT BE?

LET'S START HERE.

AND WE FOLLOW... AND WHAT DOES IT LOOK LIKE?

YES, IT'S ROUND.

AND WHAT DO YOU NOTICE?

YES, YOU ARE COMPLETELY RIGHT.

IT DOESN'T HAVE VERTICES, AND IT'S A LONG LINE.

WHAT ELSE DO YOU NOTICE?

YES!

WE END UP WHERE WE STARTED.

AND WHAT IS THIS SHAPE CALLED?

YES, CIRCLE, VERY GOOD.

LET'S CONTINUE.

MMM... [gasps] UH-OH!

ANOTHER OBSTACLE.

WHAT DO WE DO, SUPER LEARNERS?

THANK YOU.

WE HAVE TO COMPLETE IT.

A STRAIGHT SIDE, A VERTEX, ANOTHER STRAIGHT SIDE, A VERTEX, ANOTHER STRAIGHT SIDE, A VERTEX, ANOTHER STRAIGHT SIDE, AND A VERTEX.

WE'VE MADE A...

YES, SUPER LEARNERS.

A SQUARE.

OUR BUTTERFLY CAN KEEP GOING... AND IT REACHED ITS...

YES, ITS FLOWER.

NOW, THE BUTTERFLY IS FLYING AROUND, BECAUSE IT'S VERY HAPPY!

YES, SUPER LEARNERS.

IT'S HAPPY.

SO, THANKS TO YOU AND OUR FRIEND THE BUTTERFLY, WE'VE COMPLETED OUR MISSION, BECAUSE, HAPPILY, THE BUTTERFLY REACHED ITS FLOWER.

LET'S GO BACK TO SPARKLES THE FISH, TO SEE IF WE'VE COMPLETED THE MISSION.

MMM... LET'S SEE... LET'S SEE, SPARKLES.

YES!

CONGRATULATIONS, SUPER LEARNERS!

YOU USED YOUR MATH POWERS AND COMPLETED THE MISSION.

IT'S TIME TO... REVIEW.

WE LEARNED TO BUILD GEOMETRIC SHAPES IN 2 DIMENSIONS WITH DIFFERENT MATERIALS, LEARNING THEIR ATTRIBUTES, LIKE THEIR SIDES AND THEIR VERTICES.

WE ALSO WERE ABLE TO TRACE THEM CORRECTLY.

CONGRATULATIONS, SUPER LEARNERS, ON FOLLOWING US ON TODAY'S MISSION.

SPARKLES, THANK YOU, TOO.

[both] REMEMBER THAT YOU HAVE THE POWER TO BE SUPER MATHEMATICIANS!

BYE!

i¡ADIÓS!

SO, YOU'VE BEEN LEARNING A LOT SO FAR TODAY, AND YOUR BRAIN IS HAPPY.

I CAN SEE IT.

AND NOW, WE HAVE SOME MORE EXCITING THINGS FOR YOU TO WATCH.

WE ASKED SOME OF OUR FRIENDS TO PUT TOGETHER SOME VIDEOS ABOUT THINGS THAT ARE INTERESTING, AND CHECK OUT WHAT THEY CAME UP WITH.

I KNOW YOU'RE GOING TO LOVE IT.

OH, ANDRÉS, ANDRÉS.

COME OVER, COME OVER.

I WANT TO SHOW YOU.

HOLA, CRISTINA.

HOLA, ANDRÉS.

¿QUÉ ES ESTO?

(WHAT IS THIS?)

WELL, IT'S MY BALANCE.

LET'S START WITH NOTHING INSIDE THE BUCKETS.

[speaking Spanish] THERE'S NOTHING, AND... OH, LOOK, THE LINE POINTS TOWARD THE CENTER.

YEAH, YEAH, YEAH.

THE TIPS OF THE TRIANGLES MEET, SO, IT'S PERFECTLY IN BALANCE.

NOW, I'M GOING TO PUT ONE PENCIL ON THIS SIDE... YOU PUT A PENCIL THERE-- I'LL PUT THE OTHER PENCIL ON THE OTHER SIDE, TO SEE WHAT HAPPENS.

LET'S SEE.

IT'S MOVING, IT'S MOVING... [bell dings] VERY GOOD.

WE WERE TALKING ABOUT BEING IN BALANCE.

YEAH, WE'VE BEEN TALKING ABOUT BEING IN BALANCE.

AND, YOU KNOW, THESE PENCILS, THEY'RE EXACTLY THE SAME, AND THEY WEIGH THE SAME AMOUNT.

THAT'S WHY THE SCALE IS IN BALANCE NOW.

THE PENCILS ARE THE SAME, SO, NOW, I'LL PUT 2 HERE... LET'S SEE.

OF COURSE, NOW IT'S NOT BALANCED, BUT IF WE PUT ANOTHER ONE THERE, 2 AND 2... OH, LOOK, THEY'RE BALANCED.

IT'S IN BALANCE AGAIN.

WHAT IF WE TRY WITH SOMETHING OTHER THAN PENCILS?

OH, LIKE SOMETHING ELSE, NOT PENCILS?

ANDRÉS, I ALSO HAVE AN ERASER.

LOOK, YOU HAVE AN ERASER... UM, IF YOU PUT A PENCIL IN THAT BUCKET, AND I PUT AN ERASER IN THIS BUCKET, WHICH WAY DO YOU THINK THE SCALE, THE BALANCE, IS GOING TO TILT?

IF I PUT A PENCIL AND YOU PUT AN ERASER, WHICH WAY DO YOU THINK THE SCALE WILL MOVE?

LET'S SEE.

READY?

1, 2, 3.

WAS YOUR PREDICTION RIGHT?

WAS YOUR PREDICTION RIGHT?

THE ERASER IS HEAVIER.

WELL, I'M GOING TO PUT ANOTHER PENCIL, TO SEE WHAT HAPPENS.

IT DIDN'T REALLY BUDGE.

LET'S SEE.

IT'S NOT MOVING YET.

IT'S STARTING TO MOVE.

IT'S STARTING TO TILT.

BUT, LOOK, IT'S STILL NOT BALANCED.

YOU'RE RIGHT, IT'S NOT BALANCED YET.

TRY ANOTHER PENCIL.

ANOTHER PENCIL... AND... [bell dings] ESTÁ BALANCEADO.

IT'S BALANCED!

[laughs] IT'S BALANCED.

HEY, CRISTINA, SO... 4 PENCILS WEIGH THE SAME AS 1 ERASER.

ANDRÉS, WE FOUND THAT 4 PENCILS WEIGH THE SAME AS 1 ERASER.

THIS IS WHAT IT TAKES FOR IT TO BE IN BALANCE.

WHAT DO YOU THINK WOULD HAPPEN IF WE PUT 2 ERASERS IN THE BUCKET?

WHAT WOULD HAPPEN IF WE PUT 2 ERASERS?

WELL, WE'RE GOING TO NEED... HOW MANY PENCILS?

WE WOULD NEED MORE PENCILS, YOU'RE RIGHT.

4 PENCILS FOR 1 ERASER... UH-HUH.

IF WE USE 4 FOR 1 ERASER-- WELL, LET'S TRY IT.

OKAY.

HERE'S SOME MORE PENCILS.

OKAY.

LET'S SEE.

READY?

THERE'S 2 ERASERS, WE HAVE 4 PENCILS... NOW, 5... 6... 7... 8!

[bell dings] IT'S BALANCED.

SO, FOR 4 PENCILS, 1 ERASER, 4 PENCILS, 1 ERASER, 2 ERASERS WOULD NEED... HEY, ANDRÉS, CAN I BORROW MORE FINGERS?

[brrp] 2 ERASERS NEEDS... 1, 2, 3, 4... 5, 6, 7, 8.

WHAT IF WE HAD 3 ERASERS?

CRISTINA, WHERE ARE WE GOING TO GET THAT MANY PENCILS?

ANDRÉS, WE FIGURED OUT THAT IT TAKES 8 PENCILS TO BE IN BALANCE WITH 2 ERASERS.

AND WE FIGURED IT OUT BY OBSERVING.

WE OBSERVED AND LEARNED A LOT ABOUT WEIGHT AND HOW TO USE A SCALE.

THE LONGEST FRENCH FRY EVER RECORDED WAS 34 INCHES LONG.

YO, THAT'S PROBABLY BIGGER THAN SOME OF YOU AT HOME RIGHT NOW.

MATH HELPS US MEASURE HEIGHT, DISTANCE, AND SO MUCH MORE.

SO, LET'S GET INTO THAT MATH LESSON RIGHT NOW.

♪ HELLO, MATHEMATICIANS.

MY NAME IS STEPHANIE, AND I LOVE SOLVING MATH WORD PROBLEMS.

TODAY, WE'RE GOING TO READ A WORD PROBLEM, WRITE AN EQUATION THAT REPRESENTS IT, AND THEN THINK OF A STRATEGY TO SOLVE IT.

ARE YOU READY?

GREAT.

OKAY, HERE IS THE WORD PROBLEM.

YOU CAN FOLLOW ALONG WITH ME AS I READ IT.

HMM, LET'S THINK ABOUT THIS WORD PROBLEM.

WHEN I SOLVE WORD PROBLEMS, I LIKE TO THINK ABOUT WHAT'S GOING ON IN THE STORY BEFORE I TRY TO FIND AN ANSWER.

SOMETIMES, I EVEN IMAGINE MYSELF OR PEOPLE I KNOW IN THE STORY.

I HAVE A FRIEND NAMED MOESHA, AND I KNOW THAT SHE LOVES ANIMALS.

SO, I'M GOING TO IMAGINE THAT MOESHA IS AT THE PARK, COUNTING BIRDS IN THE TREES.

SHE COUNTS A TOTAL OF 55 BIRDS, WHEN MAYBE THERE WAS A LOUD NOISE THAT STARTLED THE BIRDS, CAUSING MOST OF THEM TO FLY AWAY.

AND NOW, ONLY 9 BIRDS ARE LEFT IN THE TREE, AND I WANT TO KNOW HOW MANY BIRDS ARE IN THAT GROUP THAT FLEW AWAY.

WELL... MATHEMATICIANS, SOUNDS LIKE MAYBE THERE'S A FIREWORKS SHOW AT THE PARK.

SOMETIMES THOSE LOUD CRACKING SOUNDS CAN CAUSE ANIMALS TO WANT TO GO SOMEWHERE ELSE.

CAN WE FIGURE OUT HOW MANY OF THE BIRDS FLEW AWAY TO A LESS NOISY PLACE?

YES, ABSOLUTELY, WE CAN.

LET'S DO IT.

OKAY.

WHAT SHOULD WE DO FIRST?

WHISPER IT TO ME.

I HEARD SOMEONE SAY THAT WE SHOULD FIRST WRITE AN EQUATION TO REPRESENT THE WORD PROBLEM.

AN EQUATION IS A NUMBER SENTENCE.

THAT'S A GREAT PLACE TO START.

TURN THE WORDS FROM THE STORY INTO A MATH SENTENCE.

LET'S WRITE THAT EQUATION.

WHAT WOULD THE NUMBER SENTENCE BE?

I HEARD YOU SAY: 55 MINUS BLANK EQUALS 9.

THAT'S CORRECT, BECAUSE 55 IS THE TOTAL NUMBER OF BIRDS THAT THERE ARE IN THE BEGINNING OF THE STORY AND SOME WENT AWAY, SO WE'RE SUBTRACTING, BUT WE DON'T KNOW HOW MANY WENT AWAY.

SO, THAT IS OUR UNKNOWN NUMBER.

BUT WE DO KNOW THAT THERE ARE 9 BIRDS THAT ARE LEFT.

YOU REPRESENTED THAT WORD PROBLEM VERY WELL WITH THIS EQUATION.

OKAY, SO, NOW THAT WE HAVE THE EQUATION, WHAT'S NEXT?

WHISPER TO ME WHAT MATHEMATICIANS DO NOW.

OH.

IT SOUNDS LIKE YOU WANT TO REWRITE THE EQUATION, INTO A SOLUTION EQUATION, ONE THAT WILL LEAD US TO THE ANSWER.

GOOD IDEA.

WHAT WOULD AN EQUATION BE THAT REPRESENTS HOW WE CAN GET THE ANSWER WE'RE LOOKING FOR?

I HEARD YOU SAY: 55 MINUS 9 EQUALS BLANK.

THAT'S RIGHT.

BECAUSE IF WE TAKE AWAY EITHER PARTNER, OR PART, OF A WHOLE, THEN WE'RE LEFT WITH THE OTHER PART.

THAT'S WHY THEY'RE CALLED PARTNERS.

WOW, YOU MUST BE REAL MATHEMATICIANS, BECAUSE YOU KNOW THAT WHEN YOU HAVE A TOTAL, AND YOU TAKE AWAY EITHER ONE OF ITS PARTNERS, YOU'RE LEFT WITH THE OTHER PARTNER.

BECAUSE THE PARTS TOGETHER MAKE THE WHOLE.

JUST LIKE THIS MATH MOUNTAIN SHOWS US.

MATHEMATICIANS, WHAT RELATIONSHIPS DOES THIS MATH MOUNTAIN MODEL?

RIGHT.

THIS SHOWS US THE RELATIONSHIP BETWEEN THE PARTNERS AND THE TOTAL.

WE KNOW THAT THIS PARTNER PLUS THIS PARTNER EQUALS THE TOTAL, AND THIS PARTNER PLUS THIS PARTNER EQUALS THE TOTAL, AND THE TOTAL MINUS THIS PARTNER EQUALS THE OTHER PARTNER, AND THE TOTAL MINUS THIS PARTNER EQUALS THAT PARTNER.

OKAY.

LET'S GET BACK TO OUR EQUATION, AND LET'S GET THE ANSWER.

TELL A FRIEND OR A TRUSTED ADULT WHAT WE SHOULD DO TO SOLVE, OR FIND THE ANSWER, TO THIS EQUATION.

OH!

THAT'S GOOD THINKING.

I HEARD YOU SAY THAT YOU WANT TO USE A FRIENDLY NUMBER, LIKE 10, INSTEAD OF 9, BECAUSE 10 IS SO CLOSE TO 9.

YOU'RE RIGHT.

10 IS ONLY 1 AWAY FROM 9.

WOW!

WHAT A GREAT IDEA TO USE THE FRIENDLY NUMBER 10, BEING THAT IT'S ONLY 1 MORE THAN 9.

I LOVE USING FRIENDLY NUMBERS LIKE 10.

IT WILL BE VERY EFFICIENT TO SUBTRACT 10, AND THEN, WE CAN JUST ADD 1 BACK TO THE ANSWER TO MAKE UP FOR THE 1 EXTRA WE'RE TAKING AWAY.

SO, YOU WANT TO PRETEND OUR EQUATION IS... THAT'S GREAT.

BUT WE CAN'T FORGET TO ADJUST OUR ANSWER AFTERWARDS.

SO, 55 TAKE AWAY 10 IS WHAT?

45, YOU'RE RIGHT, BECAUSE ONLY THE TENS DIGIT HAS CHANGED.

WE DIDN'T TAKE AWAY ANY ONES.

THAT IS EFFICIENT SUBTRACTION.

NOW, WHAT DO WE HAVE TO DO WITH 45?

WE KNOW THAT 45 IS NOT OUR FINAL ANSWER, BECAUSE WE HAVE TO ADDRESS THE FACT THAT WE TOOK AWAY 1 TOO MANY EARLIER.

WHAT SHOULD WE DO?

RIGHT.

I HEARD YOU SAY WE MUST ADD 1 BACK TO 45, SINCE WE REALLY TOOK AWAY 1 TOO MANY WHEN WE TOOK AWAY 10 INSTEAD OF 9, WHICH IS THE ACTUAL AMOUNT IN OUR EQUATION.

SO... 45 PLUS 1 MORE IS... YOU'RE RIGHT.

I HEARD YOU SAY 46.

THAT MEANS THAT 55 MINUS 9 EQUALS 46.

WOW!

THAT WAS AN EFFICIENT WAY TO FIND OUR ANSWER.

I LOVE HOW YOU CAN THINK FLEXIBLY ABOUT NUMBERS.

WE SOLVED THE WORD PROBLEM.

EARLIER, MOESHA TOLD ME THAT WHEN SHE WAS AT THE PARK, SHE WAS COUNTING BIRDS IN THE TREES.

SHE COUNTED A TOTAL OF 55 BIRDS, WHEN A LOUD SOUND CAUSED MOST OF THEM TO FLY AWAY.

ONLY 9 BIRDS WERE LEFT IN THE TREE.

HOW MANY BIRDS FLEW AWAY?

THAT'S RIGHT.

NOW WE KNOW THAT 46 BIRDS FLEW AWAY.

THANKS, MATHEMATICIANS, FOR HELPING ME SOLVE THIS WORD PROBLEM.

THAT WAS A LOT OF FUN.

LET'S LOOK BACK ON WHAT WE DID TODAY.

WE READ A WORD PROBLEM AND THEN WROTE AN EQUATION TO REPRESENT THAT WORD PROBLEM.

BUT THEN, WE REALIZED THAT THE EQUATION, OR NUMBER SENTENCE THAT REPRESENTED THE WORD PROBLEM IN THE ORDER OF EVENTS IN THE WORD PROBLEM, COULD BE REWRITTEN TO LEAD US TO THE ANSWER MORE EFFICIENTLY.

WE USED WHAT WE KNOW ABOUT THE RELATIONSHIPS BETWEEN PARTNERS AND THEIR TOTAL.

SINCE WE DIDN'T KNOW WHAT THE CHANGE WAS, WE SET UP AN EQUATION TO SUBTRACT THE PARTNER WE DID KNOW.

OUR NEW EQUATION, ALTHOUGH IT DIDN'T MATCH THE ORDER OF THE WORD PROBLEM, STILL LED US TO FIND THE DIFFERENCE BETWEEN THE 2 NUMBERS-- THE TOTAL AND ONE OF ITS PARTNERS.

THEN, BECAUSE WE WERE SUBTRACTING 9, AND 9 IS SO CLOSE TO 10, WHICH IS A VERY FRIENDLY NUMBER, WE SUBTRACTED 10 INSTEAD OF 9.

AFTER WE GOT THAT ANSWER, WE MADE UP FOR OUR CHANGE BY ADDING 1 BACK TO OUR ANSWER.

AND THERE WAS OUR ANSWER.

46.

WE FOUND THE OTHER PARTNER, OR PART, OF 55.

IT'S 46.

THIS WAS SUCH GREAT WORK, MATHEMATICIANS.

I LOVE BEING ABLE TO THINK FLEXIBLY ABOUT NUMBERS.

WELL, I HAVE TO GO FOR NOW, BUT I HOPE TO WORK ON MORE WORD PROBLEMS WITH YOU AGAIN SOON.

BYE!

[electronic beeps] TODAY WAS AMAZING, AND I'M SO GRATEFUL FOR YOU.

PEACE, A LITTLE BIT OF LOVE, AND A WHOLE LOT OF LEARNING, HOMIES.

BYE.

CAPTIONS BY FEATURE SUBTITLING www.featuresubtitling.com [cheerful upbeat music] ♪