Does a triangle add up to 180 or 360

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Step-by-step explanation:

Let's work backwards.

We decrease both 6 and 7 by one, then we get 5 and 6. So our new fraction is 5/6. We know that the denominator is two more than the numerator, so we have to pick numbers that are multiples of 5 and 6 and make it so the denominator is two more than the numerator.

Lucky for us we only have to multiply 5 and 6 by 2 to get an answer that works:

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