The average of all five of Carlos's test grades is exactly 84. The average of his first three grades is exactly 80. What is the average of his last two test grades? HELP HELP HELP. PLS TELL ME HOW YOU GOT THIS.

The first floor of marcus’ house is 1,440 square feet. he will cover 1,033 square feet with wood and the rest with tile. a box of tiles will cover 11 square feet. how many boxes of tile does marcus need to buy to cover the floor?

When is g(x) = 0 for the function g(x) = 5.23x + 4?

Two years ago a man was six times as old as his daughter. in 18 years he will be twice as old as his daughter. determine their present ages.