Mary bought 50 apples at the apple orchard. She bought 4 times as many red apples as green apples. How many more red apples than green apples did Mary buy?

One side of a rectangle is 7 feet shorter than seven times the other side. find the length of the shorter side if we also know that the perimeter of the rectangle is 306 feet.

The cost of using a service is $0.25 per min. what equation correctly represents the total cost c, in dollars, for d days of use?

Find the distance between the pair of points a(-1,8) and b(-8,4)