Question

Joshua sold his bike for 10% less than he paid for it. lf he sold the bike for $585, how much did he pay for it?

Answer 1

Joshua originally paid $650 for the bike.

Explanation:

The formula for determine percent change is: `p = (N - O)/O * 100` where `p` is the percent change, `N` is the new price, `O` is the old price. In this problem `p` and `N` are provided so we can substitute for these and solve for `O` while keeping the equation balanced:

`-10 = (585 - O)/O * 100`

`-10/100 = (585 - O)/O * 100/100`

`-0.1 = (585 - O)/O`

`-0.1 = 585/O - (O)/O`

`-0.1 = 585/O - 1`

`-0.1 + 1 = 585/O - 1 + 1`

`0.9 = 585/O`

`(O)/0.9 0.9 = 585/O (O)/0.9`

`O = 585/0.9`

`O = 650`