Car x traveled 144 miles and consumed 9 gallons of gas. Car y traveled 144 miles and consumed 4 gallons of gas. What is the difference between the miles per gallon of the two cars?

What is the solution of sqrt x+2-15=-3

The number if marbles of different colors stored in a hat is listed below: 4 red marbles 10 green marbles 7 blue marbles. without looking in the hat, dan takes out a marble at random. he replaces the marble and then takes out another marble from the hat. what is the probability that dan takes out a blue marble in both draws?

Gabrielle's age is two times mikhail's age. the sum of their ages is 84. what is mikhail's age?