The diagram shows a right -angled triangle and three parallel lines

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%)

How many quarts of a 50% solution of acid must be added to 20 quarts of a 20% solution of acid in order to get a 40% solution of acid?

An architect builds a model of a park in the shape of a rectangle. the model is 40.64 centimeters long and 66.04 centimeters wide. one inch equals 2.54 centimeters. use the ratio table to find the ratio of the length to the sum of the length and width in inches and in simplest form. length 40.64 width 66.04 a. 8: 21 b. 13: 21 c. 21: 13 d. 21: 8