math
posted by luis .
Mrs. Browns girls scout troop had a carwash to earn some funds. they saved 1/6 of the money. They used 1/2 of the money to go horseback riding. They then had $100 left. How much did they initially make washing cars/

If you have a certain amount of money, then take away 1/6 of that amount and 1/2 of that amount, you'll have $100. So if "M" is money.
M  (1/6))M  (1/2)M = 100
1/2 is 3/6. So
M  (4/6)M = 100
(2/6)M = 100
M = 600/2
OR...$300