The back wheel has double the spokes the front wheel has, which means the back wheel has 20 * 2 = 40 spokes. In total, the bicycle has 20 + 40 = 60 spokes.
The answer: 60
Reverse engineering the question: An unusual bicycle has 20 spokes on the front wheel and twice as many spokes on the back wheel. How many spokes does the bicycle have?


Reasoning and answer: Matt spent on math and science 30% + 40% = 70% of the time. This means he did homework from these two subjects for 70 / 100 * 150 minutes = 105 minutes. So Matt spent 150 minutes - 105 minutes = 45 minutes doing homework from other subjects.
The answer: 45
What was the question?
Question: Matt did his homework for 150 minutes. He spent 30% of that time on math and 40% on science. He spent the remaining time on other subjects. How much time did Matt spend on homework in other subjects?


If the class has 300 students, there are 40 / 100 * 300 = 120 smoking students. In a year, 70% of the smoking students are hospitalized from smoking - related complications, a total of 70 / 100 * 120 = 84 students. The number of smoking students who've not been hospitalized from smoking - related complications is 120 - 84 = 36.
The answer: 36
Reverse engineering the question: In a class of 300 students, the number of smoking teens is 40% of the class. In a year, 70% of the smoking students are hospitalized from smoking-related complications. Calculate the total number of smoking students from the class who have not been hospitalized from smoking-related complications.


Reasoning and answer: Razel received 6 x 2 = 12 shirts. Therefore, they have 12 + 6 = 18 shirts altogether.
The answer: 18
What was the question?
Question: Hazel and Razel are twins who share everything they receive. If Hazel received 6 shirts, while Razel received twice the number of shirts as Hazel. How many shirts do they have in total?


Mary spent 5 x $6 = $30 on drinks. She spent 10 x $14 = $140 on pizzas. She spent a total amount of $30 + $140 = $170. Therefore, Mary got a change of $200 - $170 = $30 after paying all the items for her pizza party.
The answer: 30
Reverse engineering the question: Mary bought 5 boxes of drinks at $6 each box and 10 boxes of pizzas at $14 each box for her pizza party. She paid $200 for all the items. How much change did she get back?


After 30 days, there will be enough food left to sustain 300 people for 90 days – 30 days = 60 days. After the 100 people leave, there will be 300 - 100 = 200 people left. The 200 people will eat 200 / 300 = 2 / 3 as much food as the original group of people in the castle. The 60 days' worth of food will last this smaller group for 60 days / (2 / 3) = 90 more days.
The answer: 90
Reverse engineering the question:
There are enough provisions in a castle to feed 300 people for 90 days. After 30 days, 100 people leave the castle. How many more days are left until all the food runs out?