In four years, Suzy will be twice Mary's age then. If Suzy is 20 now, how old is Mary?
Let's think: In four years, Suzy will be 20 + 4 = 24. Then Mary will be 24 / 2 = 12. Then Mary is now 12 - 4 = 8.. The answer is: 8.

Rob planned on spending three hours reading in preparation for his literature exam. If he ends up spending only three-quarters of this time reading, and he reads a page every fifteen minutes, how many pages did he read in this time?
Let's think: 1 hour is 60 minutes so 3 hours is 3 * 60 = 180 minutes. Three - quarters of 180 minutes is (3 / 4) * 180 = 135 minutes. He spends 15 minutes on 1 page so he will spend 135 minutes on 135 / 15 = 9 pages.. The answer is: 9.

Peter needs 80 ounces of soda for his party. He sees that 8 oz cans cost $.5 each. How much does he spend on soda if he buys the exact number of cans he needs?
Let's think: He needs 10 cans because 80 / 8 = 10. He spends $5 because 10 x .5 = 10.. The answer is: 5.

Jean has three times as much money as Jane. They have a combined total of $76. How much money does Jean have?
Let's think:
Let's assume the total amount of money that Jane has is m. Since Jean has 3 times as much money as Jane, he has 3 * m = 3m. Combined, Jean and Jane have a total of m + 3m = $76. This evaluates to 4m = $76. The total amount of money that Jane has, represented by m, is m = $76 / 4. Jane has m = $19. Since Jean has three times as much money as Jane, Jean has 3 * $19 = $57.. The answer is: 57.