Question

One month, Ruby worked 4 hours more than Isaac, and Svetlana worked 4 times as many hours as Ruby. Together they worked 104 hours. Find the number of hours each person worked.

Answer 1

Find the number ofhours each person worked.

x = Isaac hours
x + 4 = Ruby hours
((x + 4) * 4) = Svetlana hours

104 = x + (x + 4) + ((x + 4) * 4)
104 = 2x + 4 + 4x + 16
104 = 6x +20
104 - 20 = 6x + 20 - 20
84 = 6x
x = 14 hours
so
 x = Isaac hours = 14
x + 4 = Ruby hours = 14 + 4 = 18
((x + 4) * 4) = Svetlana hours = ((x + 4) * 4) =18 * 4 = 72

Prooff: 14 +18 + 72 = 104