She spend $56 because 7 x 8 = 56. She has $44 left in the bank because 100 - 56 = 44. She can get 8 five dollar bills because 44 / 5 = 8.8. This is equal to $40 because 8 x 5 = 40. She has $4 left in the account because 44 - 40 = 4.
The answer: 4
Reverse engineering the question: Emma's bank account has $100 in it. Each day of the week, she spends $8. At the end of the week, she goes to the bank and asks for as many $5 bills as her account can give her. She leaves the rest in the account. How many dollars remain in the account?


Reasoning and answer: If the number of nephews Alden had 50 years ago is half the number of nephews he has now, Alden has 50 * 2 = 100 nephews. Vihaan has 60 more nephews than Alden, meaning currently Vihaan has 100 + 60 = 160 nephews. Altogether, the two have 160 + 100 = 260 nephews.
The answer: 260
What was the question?
Question: Alden had 50 nephews ten years ago. This is half the number of nephews Alden has now. If Vihaan has 60 more nephews than Alden now, how many nephews do the two have altogether?


50cm³ will make one balloon touch the ceiling so 1800cm³ will make 1800 / 50 = 36 balloons touch the ceiling. There are 50 balloons in total so 50 - 36 = 14 balloons will not float since they were filled with ordinary air. There are 36 - 14 = 22 more balloons touching the ceiling than not.
The answer: 22
Reverse engineering the question: While preparing balloons for Eva's birthday party, her mom bought 50 balloons and 1800cm³ of helium. One balloon needs 50cm³ to float high enough to touch the ceiling, and she can fill any remaining balloon with ordinary air. If she used up all of the helium and inflated every balloon, how many more balloons are touching the ceiling than not?


Reasoning and answer: The items he returned were valued at $700 + $500 = $1200. So far he is out 3000 - 1200 = 1800 after recouping 1200. An item that is 20% more expensive cost 1 + .2 = 1.2 times as much as the item. So that means the bike he sold cost $500 * 1.2 = $600. He sold it for $600 * .8 = $480. From the bike that he had bought for 600, he was out 600 - 480 = 120. So far he is out 1800 + 120 = 1920. If he also bought a toaster worth 100, he was out 1920 + 100 = 2020.
The answer: 2020
What was the question?
Question: James buys $3000 worth of stuff from Amazon. He has to return a TV that cost $700 and a bike that cost $500. He also sells another bike that cost 20% more than the bike he returned for 80% of what he bought it for. He then buys a toaster for $100. How much is he out of pocket for everything?


The entire budget of Centerville is $3000 / 0.15 = $20,000. The budget for the parks is $20,000 * 0.24 = $4,800. After the park and the library there will be $20,000 - ($3,000 + $4,800) = $12,200 left in the budget.
The answer: 12200
Reverse engineering the question: The town of Centerville spends 15% of its annual budget on its public library. Centerville spent $3,000 on its public library and 24% on the public parks. How much is left of the annual budget?


He has to cook 115 hamburgers and has already cooked 40 so he needs to cook 115 - 40 = 75 more hamburgers. He can only cook 15 hamburgers at a time so that means he has to cook 75 / 15 = 5 more cooking sessions.
The answer: 5
Reverse engineering the question:
Ronald can grill 15 hamburgers per session on his new grill. He needs to cook 115 hamburgers in total for tonight's party. He has already cooked 40 hamburgers. How many more sessions will it take Ronald to finish cooking all 115 hamburgers?