Answer:
Isaac worked 12 hours
Ruby worked 18 hours
Svetlana worked 72 hours
Explanation:
Here in this question, we are interested in knowing the number of hours each person worked.
We proceed as follows;
Let the number of hours Isaac worked be x hours.
From the question, we are told that Ruby worked 6 hours more than Isaac
So the number of hours Ruby worked will be;
(x + 6) hours
Also;
Svetlana worked 4 times as many as Ruby:
This means that we have to multiply the number of hours Ruby worked by 4 to get the number of hours that Svetlana worked;
So the number of hours Svetlana worked will be : 4(x + 6) hours
Since the three worked a total of 102 hours, to get the number of hours each worked, we need to add together the number of hours each individual put in to work and equate to 102;
Mathematically, that would be;
x + x + 6 + 4(x + 6) = 102
2x + 6 + 4x + 24 = 102
6x + 30 = 102
6x = 102-30
6x = 72
x = 72/6
x = 12 hours
So Isaac worked x hours = 12 hours
Ruby worked (x + 6) hours = 12 + 6 = 18 hours
Svetlana worked 4(x + 6) hours = 4(18) = 72 hours