Answers
(a) 75
(b) 70
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Explanation
Rounding to 2 decimal places means we round to the nearest hundredth. The second "9" is in the hundredths place. Just to the right of that is 6, which is five or greater. Because of this, we bump the 99 to 100. That carries over to make the 74 bump to 75.
In other words, 7499 bumps up to 7500
Overall, 74.9963 rounds to 75.00 or 75 when rounding to 2 decimal places.
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Rounding to the nearest ten means 74.9963 rounds to 70
This is because 74.9963 is closer to 70 than it is to 80.
Another way to look at it: The 7 is in the tens place. Just to the right of it is 4, which doesn't meet the "five or greater" criteria. So we replace that 4 and everything to the right with 0s. We end up with 70.0000 or simply 70