Q: It costs $.10 to print one page. Jenny wants to print 7 copies of her 25-page essay. She also wants to buy 7 pens that each cost $1.50. If she pays the store with 2 twenty dollar bills, how much money should she get in change?
A: Jenny needs to print 7 * 25 = 175 pages. This will cost 175 * $.10 = $17.5. The pens will cost 7 * $1.50 = $10.50. In total, she will spend $17.5 + $10.5 = $28. Since she pays with 2 twenty dollar bills she pays with 2 * 20 = 40 dollars. Thus, she will get $40 - $28 = $12 in change. The answer is 12.

Q: Teresa scored 70 marks in science, 80 in music, 85 in social studies, and the physics exam, which was the hardest test that Teresa had ever taken in her entire life, she scored half as many marks as she scored in music. Calculate the total marks Teresa scored in all the subjects.
A: The total marks of science and music are 70 + 80 = 150. When you add the marks she scored in social studies, the full marks become 150 + 85 = 235. She scored half as many marks in physics as she scored music, totaling 1 / 2 * 80 = 40 marks. When you add the marks she scored in physics to the total marks of the other subjects, the full marks become 235 + 40 = 275. The answer is 275.

Q: Susan has 3 fish tanks to fill. 1 fish tank contains 7 goldfish and 8 beta fish. The second fish tank contains twice as many fish as the first tank and the third fish tank has a third of the number of fish in the second fish tank. How many fish are in the third fish tank?
A:
In the first fish tank, there are 7 goldfish + 8 beta fish = 15 fish. The second fish tank therefore has 15 fish in the first tank * 2 = 30 fish. So the third tank has 30 fish in the second fish tank / 3 = 10 fish. The answer is 10.