"The sum of 2 numbers is 37" so, [x + y = 37]
"One is 15 more than the other number" so, [y = x + 15], or [x = y + 15]
With two equations and two variables we can usually find the answer.
x + y = 37
y = x + 15
Substitute the second equation in for the 'y' in the first equation:
x + [y] = 37
x + [x + 15] = 37
2x + 15 = 37
2x = 37 - 15
2x = 22
x = 11
Now that you know x, use either equation to solve for y.
y = x + 15
y = 11 + 15
y = 26.
26 + 11 = 37
So the correct answer is C) 11 and 26