If there were 1500 surfers on the first day, the total for the second day is 1500 surfers + 600 surfers = 2100 surfers. On the third day, the number of surfers was 2 / 5 * 1500 surfers = 600 surfers. The total number of surfers at the Festival in the three days was 1500 surfers + 2100 surfers + 600 surfers = 4200 surfers. The average number of surfers at the Beach Surf Festival for the three days is 4200 surfers / 3 days = 1400 surfers / day.
The answer: 1400
Reverse engineering the question: Surfers enjoy going to the Rip Curl Myrtle Beach Surf Festival. There were 1500 surfers at the Festival on the first day, 600 more surfers on the second day than the first day, and 2/5 as many surfers on the third day as the first day. What is the average number of surfers at the Festival for the three days?


Reasoning and answer: Class A is twice the size of Class B, so Class A = 2 * size of Class B. If Class B has 20 people Class A has 20 * 2 = 40 people. Since Class A is also 1 / 3 the size of Class C then Class A = 1 / 3 * Class C. This means 40 = 1 / 3 * Class C. Thus the size of Class C is 3 * 40 = 120 people.
The answer: 120
What was the question?
Question: Class A is twice as big as Class B. Class A is also a third the size of Class C. If Class B has 20 people in it, how many people are in Class C?


Julian's number of friends who are girls is .40 * 80 = 32. Boyd has twice as many friends as Julian who are girls, a total of 2 * 32 = 64. If Boyd has 100 friends, he has 100 - 64 = 36 boys. The percentage of boys in Boyd's Facebook friends is 36 / 100 * 100 = 36.
The answer: 36
Reverse engineering the question: Julian has 80 Facebook friends. 60% are boys and 40% are girls. Boyd has twice as many friends who are girls and has 100 friends total. What percentage of Boyd’s friends are boys?


Reasoning and answer: He uses 1 tablespoon for weak coffee and doubles that for strong so the strong uses 1 * 2 = 2 tablespoons. For the weak coffee he uses 1 tablespoon per 1 cup of water and he needs to make 12 cups so he'll use 1 * 12 = 12 tablespoons. For the strong coffee he uses 2 tablespoons per 1 cup of water and he needs to make 12 cups so he'll use 2 * 12 = 24 tablespoons. All total he will use 12 tablespoons for the weak coffee and 24 tablespoons for the strong coffee for a total of 12 + 24 = 36 tablespoons.
The answer: 36
What was the question?
Question: Half of Taylor's house guests like weak coffee and the other half like strong coffee in the morning. Taylor uses 1 tablespoon of coffee per cup of water to make it weak and he doubles that amount to make it strong. If he makes 12 cups of both weak and strong coffee, how many tablespoons of coffee will he need?


There are 4 quarters in a dollar so in quarters, each machine holds 80 quarters / 4 = $20. There are 10 dimes in a dollar so in dimes, each machine holds 100 dimes / 10 = $10. Each machine therefore holds $20 in quarters + $10 in dimes = $30. So Erin must therefore have $90 total income / $30 income per machine = 3 machines.
The answer: 3
Reverse engineering the question: Erin runs her own launderette and needs to cash in the change from the machines. There are 80 quarters and 100 dimes in every machine in the launderette. When Erin empties all of the machines and cashes in the change, she has a total of $90. She had no money before she emptied the machines and each machine held the same amount of money. How many machines are in the launderette?


Bert was able to earn 8 x $18 = $144 for the toy phones. While Tory was able to earn 7 x $20 = $140 for the toy guns. Therefore, Bert was able to earn $144 – $140 = $4 more than Tory.
The answer: 4
Reverse engineering the question:
Bert was able to sell 8 toy phones for $18 each, while Tory was able to sell 7 toy guns for $20 each. How much more did Bert earn than Tory?