Answer is 538.8
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How to get this answer:
The first step is to locate the tenths decimal place, which just to the right of the decimal point. So the "7" is in the tenths place.
Look one spot further to the right. We see the value 8 here. Since 8 is larger than 5, it tells us to bump the prior "7" up by 1 and
This means 538.78 turns into 538.8
You can think of it as saying "78 is closer to 80, rather than 70" which is why we round the "0.78" portion up to "0.80"
note: 538.8 is the same as 538.80; the zero at the end has no effect on changing the value.