18 Estimate 8128 /18 by first rounding each number so that it has only nonzero digit.
20. Find the digits in the tens place, in the tenths place, and in the ten thousandths place for the following number. 465.2587
18. If you are going to round, why "none zero" digit?
8000/20 = 400
20. 6, 2 and 7 respectively