Mr. tuyen uses 5/8 of a tank of gas each week to drive to and from his job. how many tanks of gas does mr. tuyen use in 5 weeks? write your answer in two different ways

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

If t17 = 3 (t5) in an arithmetic progression, find t1 in terms of d.

Two airplanes start at the same place and travel in opposite directions,one at 395 miles per hour and the other at 422 miles per hour. how many hours will it take for the planes to be 2451 miles apart?