Question: Peter is buying a set of glasses. They cost $3 for small glasses and $5 for large ones. He has $50. If he buys 8 small ones and leaves with $1 in change, how many large ones did he buy?
Answer: He spent $49 on glasses because 50 - 49 = 1. He spent $24 on small glasses because 8x3 = 24. He spent $25 on large glasses because 49 - 24 = 25. He bought 5 large glasses because 25 / 5 = 5. The answer is 5.

Question: Bart fills out surveys to earn money. He receives $0.2 for every question he answers in the survey. Each survey has 10 questions. On Monday he finished 3 surveys, and on Tuesday 4 surveys. How much money did he earn during these two days?
Answer: On Monday and Tuesday Bart finished 3 + 4 = 7 surveys. Each survey has 10 questions, so he answered 10 * 7 = 70 questions. Bart gets paid $0.2 for each questions, so he earned 70 * $0.2 = $14. The answer is 14.

Question: Thomas is keeping track of the rainfall in May for his science project. On the first day, 26 cm of rain fell. On the second day, 34 cm fell. On the third day, 12 cm less than the second day fell. The average rainfall for the first three days of May is usually 140 cm across all three days, in a normal year. How much less is it raining this year than average?
Answer: In total 26 + 34 + 22 = 82 cm fell for three days. If 140 cm is the average for the first three days, then 140 - 82 = 58 cm less than the average. The answer is 58.

Question: Daria wants to go to a concert by her favorite band. She wants to buy tickets for her and for three of her friends. One ticket cost is $90. How much money does Daria need to earn if she currently has only $189?
Answer:
Daria wants to buy tickets for four persons, so the cost will be 4 tickets * $90 / ticket = $360. Daria currently has $189, so she needs $360 - $189 = $171 more. The answer is 171.