Question

estimate 21% of 199

Answer 1

Try rounding 199 to the nearest number ending in 0 and take 21% of that. For example, 21% of 100 is 21.

Answer 2

you can also take 21% and round that down 20% right?

Answer 3

You could, but the larger the number you're dividing, the further from the proper answer your estimate will be. Just keep that in mind, always show your reasoning, and look for what your teacher or professor is asking.