write 0.4% as a fraction or mixed number in simplest form.

Solve this system of equations. 12x − 18y = 27 4x − 6y = 10

How long must $542 be invested at a rate of 7% to earn $303.52 in interest? in a easier way

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.