Reasoning and answer: The miles that Terry drives daily from home and back are 60 * 2 = 120 miles. The hours he takes driving from home and back are 120 / 40 = 3 hours.
The answer: 3
What was the question?
Question: Terry drives at a speed of 40 miles per hour. He drives daily forth and back from his home to his workplace which is 60 miles away from his home. How many hours does Terry spend driving from home to the workplace and then back?

Reasoning and answer: The amount that the couple would cover for the hospital bill is $128 / 2 = $64. The couple's total expenses (salary and hospital bill) is $160 + $64 = $224. So each of them should give $224 / 2 = $112 in total. Since the husband paid the entire half of the hospital bill already ($64), he still needs to pay $112 - $64 = $48.
The answer: 48
What was the question?
Question: A couple agreed to split their expenses equally, including the salary of their house help. While doing her job, the house help had an accident; thus, she underwent a medical procedure which cost her $128. The couple decided to pay half of the medical expenses and the other half will be deducted from her $160 salary. If the husband paid for the entire half of the hospital bill, how much does he still need to pay so that they split the expenses for the house help equally?

Reasoning and answer: The number of short students in the class is 2 / 5 * 400 = 160. The total number of short and tall students is 160 + 90 = 250. Since there are 400 students in the class, the number of students with average height is 400 - 250 = 150.
The answer: 150
What was the question?
Question:
The number of short students in a class is 2/5 of the total number of students. If there are 90 tall students, and the class has 400 students, calculate the total number of students with average height.