Fractions - multiplying, dividing, adding, subtracting and finding the fraction of an amount

Leaning about X,+,- and dividing fractions. As well as finding a fraction of something.

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Multiplying Fractions.

Multiply the top of each fraction and then the bottom.

eg: 3/5 X 4/6

= 3X4 / 5X6

= 12/30

(simplyify) = 4/10

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Dividing Fractions.

"flip and times"

eg: 5/8 divided by 6/4

= 5/8 X 4/6

^ we've flipped the second fraction and now we multiply.

= 5X4 / 8X6

= 20/48

(simplyify) = 5/12



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Adding and Subtracting Fractions.

Denomiaters are the same! MAKE SURE BOTTOM NUMBERS ARE THE SAME.

eg: 2/8 + 2/4 (what do both 8 and 4 go into? well 4 goes into 8 twice and 8 goes into 8 once.)

= 2/8 + 2/ (but DO NOT FORGET that to get the same denominaters we X 4 by 2 and 8 by 1, so we have to do the same to the top.)

= 2x1/8 = 2/8 and 2X2/8 = 4/8

(now plus the top numbers) = 2+4/8

= 6/8

(simplyify) = 3/4

SUBTRACTING IS THE SAME BUT INSTEAD OF ADDING THE TOP NUMBERS TOGETHER YOU SUBRACT THEM.

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Finding a fraction of an amount.

amount = N

Multiply N by the top number of the fraction and then divide that by the denominater.

eg: 2/10 of £480 (or 1/5 of £480)

= 2 X 480 = 960

= 960 divided by 10 = 96

Answer = £96

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Comments

Jordan Young

never understood this until know, thank you.

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