Alex weighs 85 pounds. Together, he and his sister weigh ten pounds more than five times the weight of his sister. What is the weight, w, of Alex's sister?
Options
A) 85 + w=5w - 10; 25lb
B) 85 + w - 10=5w; 7.5lb
C) 85 + w=5w; 28lb
D) 85 + w=5w + 10; 15lb
Let's represent Alex's weight as A and his sister's weight as S.
Given that Alex weighs 85 pounds, A = 85.
Together, he and his sister weigh ten pounds more than five times the weight of his sister: A + S = 5S + 10.
Substitute A = 85 into the equation above, we get: 85 + S = 5S + 10
Combine like terms: 75 = 4S
Divide both sides by 4: S = 18.75 lb
The weight of Alex's sister is 18.75 lb, so none of the provided options are correct.