To solve the problem, what you must do is a system of two equations with two Ingonites that describe the problem.
Let:
x = number of shirt buttons.
y = number of buttons on jackets.
Writing the system:
36x + 42y = 842
6x + 7y = 137
We observe that the system is linearly dependent, therefore, it can not be solved.
However, the solution is to solve the system of two equations with two unknowns.
In order to solve it, the system must be linearly independent.
The answer is D. 15+18+12+5= 50 and there are 5 ramblers