21 is 75% of what number?

I don't get it.

One light year is 5.88*10^12 miles. star 2030 is 5.885*10^13 miles from planet x. how many light year is it from planet x to star 2030

Mr. Gleason's math class lasts 40 minutes. Math class starts at 9:55 A. M. At what time does math class end?

You work at a grocery store. Last week, you sold 213 potatoes to customers and lost 6 potatoes due to expiration. The store paid $0.47 per potato and sold each potato for &0.88. What profit did the store make on potatoes last week?

Solve the equation. 31-12n=211

Comparing and ordering rational numbers

How much volume is in 250 ml of water

A frame around a rectangular family portrait has a perimeter of 150 inches. The length is ten more than four times the width. Find the length and width of the frame.

In two hours, Holden completed 3/4 of his race. How long will it take Holden to complete the entire race.

0.506 rounded to the nearest hundredth

John had 5 houses. he sold 1/5 of them. how many are left?