Question 98
All you have to do is express it as equations:

Maria + 7 = 4*(Angelica +7)
Maria + Angelica = 71

Replace Maria with M and Angelica with A

M=4*A = -7-4*7
M+A   = 71

This is a classic linear system of equations, for which I have a <A HREF=http://www.algebra.com/algebra/homework/coordinate/>solver that shows work</A>.