Mrs. Winthrop went to a store, spent half of hermoney and then $ 10 more. She went to a second store, spent half of her remaining money and $ 10 more. But she then had no money left. How much money did she have to begin with when she went to the first store?
Let the original of money =M
1/2M + 10 =She spent at the first store.
M - [1/2M+10]=[M - 20]/2 -what she had left after the first store,
(M - 20)/2 =1/2(M - 20)/2 + 10, solve for M
M = $60 - The original amount of money she started with.
Check: $60/2 + 10 =$40 what she spent at first store.
$60 - $40 =$20 she had left after the first store.
$20 / 2 + $10 =$20 what she spent at the 2nd store.
$20 - $20 =0 - what she had left after the 2nd store.