24 is 3/4 of what number?

Please help

The sum of the speeds of two trains is 720.2 mph. if the speed of the first train is 7.8 mph faster than the second train, find the speeds of each.

Abaseball team drinks 10/4 gallons of water during a game. which mixed number represents the gallons of water consumed? a) 1 1/2 gallons b) 2 1/2 gallons c) 2 3/4 gallons d) 3 1/2 gallons

Why is x= 4 a solution to the proportion 14/x 56/1 6