If we assume the number of hours Isaac worked is x hours. So in that case the number of hours Ruby worked must be 6 + x. And similarly Shetland worked around 4 (6+x) hours.
So we can easily form an expression that gives us how many hours each worked. So basically x + 6 + x + 24 + 4x = 126. So 6x = 96/6 = 16.
SO Isaac worked for 16 hours. Rudy worked for 22 and Shetland worked for the rest.
