Answer: Choice C
4/6 = 8/12
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Step-by-step explanation:
Let's go through the answer choices
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Choice A.
Assume that the given equation here is correct. If so, then we can cross multiply to get
2/3 = 4/9
2*9 = 3*4
18 = 12
The last equation is false, so the first equation is also false. Choice A is not the answer.
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Choice B.
We could do the similar trick as with choice A, but I'll use another method.
Use your calculator to find that
5/7 = 0.714 approx
10/11 = 0.909 approx
We get different decimal values for each fraction, so there's no way the two sides are the same. Choice B is crossed off the list.
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Choice C.
I'll use another method here. Note how the denominators are 6 and 12, and how 6*2 = 12. If we multiply top and bottom of 4/6 by 2, then
(4/6)*(2/2) = (4*2)/(6*2) = 8/12
meaning that 4/6 = 8/12 is a true equation. We can see it through cross multiplication
4/6 = 8/12
4*12 = 6*8
48 = 48
or we could use our calculator to find that
4/6 = 0.667 approx
8/12 = 0.667 approx
Another calculator trick you can use is type in "4/6 - 8/12" without quotes and you should get 0 (or very close to it) as a result. This is using the idea that if x = y, then x-y = 0.
Choice C is the answer
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Choice D.
Since we found the answer, we technically don't need to check choice D. But let's do so anyway.
Right off the bat, we know that 3/4 is less than one, while 12/9 is greater than one. So there's no way 3/4 = 12/9 could be true.