Order 3/2, 5/8, 9/4, 1 & 7/8 from least to greatest

Ineed with this problem 21 show steps

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%)

Using the rise/run counting method, the slope of the line is