A rectangular field will be fenced on three sides leaving a side of 20 feet uncovered . If the area of the filed is 680 square feet, how many feet of fencing will be required?

The selling price of 15 items equals the cost of 20 items. What is the percentage of profit earned by the sell...

The length of a rectangular room is double of its breath. If the area is 512 square inches, what is the perime...

A class had 30 students. The class needs to select 3 represntatives. In how many ways can this be done?

In a group of 15,7 have studied Latin, 8 have studied Greek and 3 have not studied either. How many of these s...

A student multiplied a number by 3/5 instead of 5/3. What is the percentage error in the calculation.

The different between two numbers is 5 and the different between their squares is 65. What is the larger numbe...