X-13=42
x is the "variable", you're taking 13 away from that, and the answer is also given, 42.
The answer is 16. 7 is 1/4th the value of 28, so 4 should be 1/4th the value of 16.
4 is 16.3, I don't know 5 or 6, 7 is 176, I don't know 8 or 9, 10 is 8.1, I don't know 11, and 12 is 48.
(I used a calculator, lol)
