# Thread: Can't Find Cost Price

1. ## Can't Find Cost Price

I can't find the proper working for this. If you know how to get to the answer, could you show your steps for working? Thanks.

Problem:
Jake sells his car for $3500. He makes 20% profit. What was the price Jake bought the car for? 2. Originally Posted by .Twilighted. I can't find the proper working for this. If you know how to get to the answer, could you show your steps for working? Thanks. Problem: Jake sells his car for$3500. He makes 20% profit. What was the price Jake bought the car for?
Originally Posted by .Twilighted.

Problem:
Jake sells his car for $3500. He makes 20% profit. What was the price Jake bought the car for?$\displaystyle P+B=3500$the percentage(interest) + the original price(base) =$3500

remember the to find the original price divide the percentage by the rate.

$\displaystyle B=\frac{P}{R}$

to find the percentage multiply rate by the original price

$\displaystyle P=\frac{R}{B}$

$\displaystyle P+B=3500$

substitute P with R*B. interms of rate and base

$\displaystyle R*B+B=3500$

$\displaystyle 0.20*B+B$

$\displaystyle 1.20B=3500$

$\displaystyle B=\$2916.66$original price check$\displaystyle \$2916.66*.20=583.33$ = P

$\displaystyle B+P=\$3500\displaystyle \$2916.66+583.33=\$3499.99$or$\displaystyle \$3500$

this is how i solved it,
the original price/cist price is $\displaystyle \$2916.66\$