Q: A train travels 360 miles in 3 hours. At the same rate, how many additional hours would it take to travel an additional 240 miles?
A: The rate is 360 / 3 = 120 mph. Then it would take 240 / 120 = 2 additional hours. The answer is 2.
Question: Paul is collecting license plates from different states. He has plates from 40 different states. For each percentage point of total US states that he has, his parents will give him $2. How much does he earn from them?
Answer: The proportion of plates that he has out of total states is .8 because 40 / 50 = .8. He has 80% of the plates because .8 x 100 = 80. He makes $160 because 80 x 2 = 160. The answer is 160.
[Question]Alissa used discarded paper to make notepads for her friends. She would fold 5 pieces of letter-size paper 3 times then cut along the edges to form smaller note papers. She would then stack these smaller note papers and staple them together. How long would 1 notepad last if someone wrote 10 notes per day?
[Answer]Alissa folding it 3 times makes 2 × 2 × 2 = 8 pieces of note - size paper per letter - size paper. So 5 pieces of letter - size paper make 5 × 8 = 40 pieces of note - size paper. 1 note pad would last 40 ÷ 10 = 4 days if someone wrote 10 notes a day. The answer is 4.
Q: Of the 24 students in class, one-third are in the after-school chess program, and half of those students will be absent from school on Friday for the regional chess tournament. How many of the students in this class are going to that tournament?
A: There are 24 / 3 = 8 students in the program. And 8 / 2 = 4 go to the tournament. The answer is 4.
Question: Percius has a collection of marbles. 40% of them are clear. 20% are black, and the remainder are all the other colors. A friend of his asks if he can take five marbles. On average, how many marbles of other colors will his friend end up getting?
Answer: 40% of the marbles are of other colors because 100 - 20 - 40 = 40. The friend will on average get 2 other colored marbles because 5 x .4 = 2. The answer is 2.
Q: There are 20 students in the class. Half of them play basketball. Two-fifths play volleyball and one-tenth play both basketball and volleyball. How many students in this class do not play either game?
A:
Half of the students are playing basketball, which means 20 / 2 = 10 students play basketball. Two - fifths plays volleyball, which leaves us with 20 * 2 / 5 = 8 students. One - tenth play both games, which means 20 * 1 / 10 = 2 students. There are 10 + 8 = 18 students who play basketball or volleyball. Among these 18 students, 2 of them are playing both games, so that means 18 - 2 = 16 students play only one of the two games. So finally, 20 - 16 = 4 students do not play either game. The answer is 4.