Question: 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.
Answer with step-by-step thinking: 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.
So the answer is 275.


Question: John decides to fix a racecar. It cost $20,000 to fix but he gets a 20% discount. He wins his first race but only keeps 90% of the money. The prize is $70,000. How much money did he make from the car?
Answer with step-by-step thinking: He gets a 20000 * .2 = $4000 discount. So he paid 20000 - 4000 = $16000. He kept 70000 * .9 = $63000. So he made 63,000 - 16,000 = $47,000.
So the answer is 47000.


Question: Olga has an aquarium with fish in 5 different colors. There are 12 yellow ones, half as many blue ones, and twice as many green ones as yellow ones. How many fish does Olga have in her aquarium?
Answer with step-by-step thinking:
Olga has half as many blue fish as yellow ones, which means 12 * 0.5 = 6 blue fish. Green fish are twice as many as yellow ones, so in total there are 12 * 2 = 24 green fish. So all the fish sum up to 12 + 6 + 24 = 42.
So the answer is 42.