Math
posted by Miley on .
need to describe 3 different problem solving approaches to this problem, one I think is algebra, but don't know how to solve, and i need to say how to solve each one in each different way, please help with this.
aaron is thinking of a number, if its doubled, increased by 10, cut into thirds, and reduced by 7, new number is 5, whats original number?

n = original number
( 2 * n + 10 ) / 3  7 = 5 Add 7 to both sides
( 2 n + 10 ) / 3  7 + 7 = 5 + 7
( 2 * n + 10 ) / 3 = 12 Multiply both sides by 3
2 n + 10 = 12 * 3
2 n + 10 = 36 Subtract 10 to both sides
2 n + 10  10 = 36  10
2 n = 26 Divide both sides by 2
n = 13
( 2 * n + 10 ) / 3  7 =
( 2 * 13 + 10 ) / 3  7 =
( 26 + 10 ) / 3  7 =
36 / 3  7 = 12  7 = 5