Question

Mary waits tables at a dinner every weekend to make extra money. She donates 20% of her tip to her favorite charity and then keeps the rest. Last weekend Mary earned $250 in tips. How much money did Mary keep to herself last weekend? A) $200 B) $125 C) $50 D) $25

Answer 1

250/5=50
20% is same as 1/5
1-1/5=4/5
4/5 is equal to 80%
4 times 50 = 200
Mary kept 200 dollars to herself 

Answer 2

(250x.2)=50
250-50=200