Robert earns $512.75 less than the salary earned by noel. john earns three times robert's salary. if the total salary earned by them is $47,645.25, how much salary do robert earn?

$9426.50

Step-by-step explanation:

let noel's salary = x, robert's salary = y and john's salary = z

y = x - 512.75 (1)

z = 3y = 3(x - 512.75) = 3x - 1538.25 (2)

x + y + z = 47645.25(3)

substitute for y and z

x + (x - 512.75) + (3x - 1538.25) = 47645.25

x + x - 512.75 + 3x - 1538.25 = 47645.25

5x = 47645.75 + 512.75 + 1538.25

5x = 49696.25

divide both sides by 5

x = 9939.25 noel's salary

to get robert's salary substitute x in equation 1

y = 9939.25 - 512.75 = 9426.50

y = $9426.50 robert's salary