#1

Mr. Jones got a loan for a sum of money, and at the time of repayment he owed $75 in interest. Mr. Brown borrowed three times the amount of money Mr. Jones had borrowed at the same rate of interest for twice as long a time. How much interest does Mr. Brown pay?

#2
Mr. Baker earns $448 a week. He spends 86% of this amount for expenses. The amount he saves in a year of 52 weeks is.

#3
In a high school there are 768 pupils. Of these, 3/8 are girls. If 5/6 of the girls are below the senior class, the number of senior girls is.

#4
Last month, Nate spent 12% of his paycheck on car repairs and 25% of the remainder on food. He gave $1320 of the remaining money to his parents and then bought a computer on sale. If the usual price of the computer was $825 and the discount was 20%, how much money did Nate have in the beginning?

1 answer

Just translate the words to algebra. Then solve. For example,

#3:
3/8 of 768 = 288
5/6 are below senior, so 1/6 are seniors.
1/6 of 288 = 48

Where do you get stuck on the others?