A number is four less than two times the other number.

A number is four less than two times the other number. If their difference is 21, what is the greater number?

Quiz

Answer/Solution

46

Steps/Work

A = one number
B = other number
A = -4 + 2B
A - B = 21
solve for A by adding B to each side
A = B + 21
Substitute (B + 21) for A in A = -4 + 2B
(B + 21) = -4 + 2B
add -B to each side
21 = -4 + B
add 4 to each side
25 = B
Since A = B + 21 , A = 25 + 21 , A = 46
ANSWER:B