How much pure acid should be mixed with 55 gallons of a 60%acid solution in order to get an 80% acid solution?

There are four numbers is A. P, the sum of the two extremes is 8, and the product of the middle two is 15. What are the numbers

A rectangle game board is 12 1/4 square inches. Its length is 3 1/2. What is the width of the board?

There are 25 students in mrs. Murphys math class, of these students 10 have brown hair, 8 have black hair, 5 have blonde hair, and 2 have red hair. what percentage of students in mrs. Murphys class have black hair?

Divide 56 yd in the ratio 4:7:3

In March Tom had - £165 in his bank account. In April he had - £156. In which month did he have the least amount of money in his account?

What number is 62.5% of 195?

2/w=0.4/0.7 what is w?

2.6 as an improper fraction

The length of a rectangle is 7cm less than twice it's width. If the area is 30 sq. cm, find the dimensions

Heights of 10 year-olds, regardless of gender, closely follow a normal distribution with mean 55 inches and standard deviation 6 inches. Which of the following is true? Roughly 95% of 10 year-olds are between 37 and 73 inches tall.