Abel, Belle, And Cindy have $408 altogether. Belle has $7 more than Cindy and $5 more than Abel. How much does Abel have?

2 answers

a+b+c = 408
b = c+7
b = a+5

now crank it out.
a + b + c = 408
b = c + 7 so c = b-7
b = a + 5

a + (a+5) + (a+5-7) = 408

3 a + 3 = 408

a + 1 = 136

a = 135