Estimate the sum by rounding each number to the given place value.
164,215+216,088 rounded to the nearest ten thousand

Barbara deposited $300 in the bank. if the bank pays her simple interest at the rate of 4 percent per year, how much money will she have in her account at the end of 9 months?

How can you construct perpendicular lines and prove theorems about perpendicular lines

Acircle has a circumference of 7.850 units. what is its radius?