Suppose Matthew Whitaker performs on a rectangular stage with an area of 1815 square feet. If the length of the stage is 5x and the width of the stage is 3x, what is the value of x?

Astudent must have an average on five test that is greater than it equal to 80% but less than 90% to receive a final grade of b. devon's greades on the first four test were 78% 62% 91% and 80% what range if grades on the fifth test would give him a b in the course? ( assuming the highest grade is 100%)