How do i get from 51/125 to 408/1000?

Which of the following expressions is equal to 2x^2+8

Big boi and travis scott are performing at the super bowl. travis scott is 62 years younger than twice big boi’s age. the sum of their ages is 70 years old. use b to represent big boi’s age. write and solve an equation.

A33 gram sample of a substance that's used to detect explosives has a k-value of 0.1473. n = noekt no = initial mass (at time t = 0) n = mass at time t k = a positive constant that depends on the substance itself and on the units used to measure time t = time, in days