math
posted by Anonymous on .
jim is 45 years old. He is 10 years older than 5 times his niece. How old is carol?

J = Jim age
C = Carol age
J = 45
J = 10 + 5 C
45 = 10 + 5 C Subtract 10 to both sides
45  10 = 10 + 5 C  10
35 = 5 C Divide both sides by 5
35 / 5 = C
7 = C
C = 7
Carol is 7 yo
Proof :
5 * 7 + 10 = 35 + 10 = 45 
Mark has received a tax refund. He used 1/4 of the money to pay off his credit card. Than he spent 1/3 of the remaining money on new clothes and shoes for his kids. After shopping he used 1/5 of what was left to go out to eat. Finally, donated 1/2 of what was left to the food bank. This all left Mark with $128. How much did Mark receive?