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Question

How would you multiply 11/15 and 12/17?

2 years ago

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1 Reply

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1438 views

E

Eliane Johnston


1 Answer

V
Victoria Agule

'horizontal multiplication' is required when multiplying fractions.

So the sum is essentially this: 11x12 / 15x17


11x12: mutliply 12 by 10 (so add a zero at the end); add 12 x 1(so 12) to that number; the answer is 132


15x17: if you are familiar with square numbers you'll know 15 x 15 is 225; 15 x 2 is 30; add these two; the answer is 255


answer = 132/255


If the question asks for simplification:

start with the smallest number, so 132.


Ask: can this be divided by 2? yes.

Then: can 255 be divided by 2? no (it ends in 5)

move through consecutive numbers


answer = 44/85

both can be divided by 3

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