Why would you rather round to the nearest hundred than the nearest ten?

Rounding is selected to match the precision required. Rounding to the nearest hundredth provides better precision than rounding to the nearest tenth.

Explanation.
Suppose you calculate the value of a variable x as $300.0143.

Because $0.143 or 14.3 cents is not available, we round 14.3 cents to 14 cents, and x = $300.14.
In this case, we have rounded to the nearest hundredth.

If you do not want to be bothered with pennies, you ignore the four pennies and round 14 cents to 10 cents, and x = $300.10. 
In this case, we have rounded to the nearest tenth.

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