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Lucy wants to multiply 88 x 808. She says that all she has to do is find 8 x 808 and then double that number. Explain why Lucy's method will not give the correct answer. Then, show how to find the correct answer.

User Rogue Lad
by
8.1k points

1 Answer

1 vote

The multiplication that Lucy has to make is:


88*808

If she multiplies 8x808 and then multiplies the result by 2, she will not be finding 88x808, instead, she will be finding 16x808, (because 8x2 is 16):


2(8*808)=16*808

Thus, with that method, she will not get the correct result.

Let's find the correct method:

Going back to the original multiplication she has to make:


88*808

We can express the number 88 as 11x8:


(11*8)*808

And we represent this as follows:


11(8*808)

And we have found the correct method: she has to find 8x808 and then multiply the result by 11.

Answer: Find 8x808 and multiply the result by 11.

User His Royal Redness
by
7.6k points
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