If ratios can be written as fractions, why are not all fractions ratios

Four airplanes carrying a total of 400 passengersarrive at the detroit airport. the airplanes carry, respectively,50, 80, 110, and 160 passengers. a) one of the 400 passengers is selected uniformly at random. let x denote the number of passengers that were on theairplane carrying the randomly selected passenger. find var(x)for x as given in the problemb) one of the 4 airplane drivers is also selected uniformly atrandom. let y denote the number of passengers on the chosen driver’s airplane. find var(y) for y as given in the problem

What value of x is in the solution set of 4x - 12 s 16 + 8x? -10 -9 -8 -7

Using only odd number for numerators write two different subtraction problems that have a difference of 3/4