[Question]Jake amasses a fortune of 80 bitcoin. He donates 20 bitcoins to charity. He then gives half of all the bitcoins to his brother. After that, he triples the number of bitcoins he has. Then he donates another 10 coins. How many coins does he have?
[Answer]He had 80 - 20 = 60 after the donation. He kept 60 / 2 = 30 after giving half to his brother. So he has 30 * 3 = 90 coins. He then does 1 more donation and has 90 - 10 = 80 coins left. The answer is 80.
Q: Yolanda leaves home for work at 7:00 AM, riding her bike at 20 miles per hour. 15 minutes after she leaves, her husband realizes that she forgot her lunch, and jumps in the car to bring it to her. If he drives at 40 miles per hour and follows the exact same route as Yolanda, how many minutes will it take him to catch her?
A: Let x be the number of minutes it takes Yolanda's husband to catch her. We know that Yolanda will spend a total of x + 15 minutes riding her bike since she left 15 minutes before her husband. The distance each person travels is equal to their travel speed times the number of minutes they spend traveling. That means Yolanda's distance is equal to 20 mph * (x + 15) and her husband's distance is equal to 40 mph * x. Yolanda's husband catches up to her when they've both traveled the same distance, which is when 20(x + 15) = 40x. We can simplify this equation by multiplying 20 through the parentheses to get 20x + 300 = 40x. Then we can subtract 20x from each side to get 300 = 20x. Finally, we divide both sides by 20 to find that x = 15. The answer is 15.
Question: Tim has 30 less apples than Martha, and Harry has half as many apples as Tim. If Martha has 68 apples, how many apples does Harry have?
Answer: Tim has 68 - 30 = 38 apples. Harry has 38 / 2 = 19 apples. The answer is 19.
[Question]Joy can read 8 pages of a book in 20 minutes. How many hours will it take her to read 120 pages?
[Answer]In one hour, there are 3 sets of 20 minutes. So, Joy can read 8 x 3 = 24 pages in an hour. It will take her 120 / 24 = 5 hours to read 120 pages. The answer is 5.
Q: Each bank teller has 10 rolls of coins. Each roll has 25 coins. How many coins do four bank tellers have in all?
A: Each bank teller has 10 x 25 = 250 coins. Thus, four bank tellers have 250 x 4 = 1000 coins. The answer is 1000.
Question: If Buzz bought a pizza with 78 slices at a restaurant and then decided to share it with the waiter in the ratio of 5:8, with Buzz's ratio being 5, what's twenty less the number of slices of pizza that the waiter ate?
Answer:
The total ratio representing the slices of pizza that Buzz bought is 5 + 8 = 13. If he shared the slices of pizza with the waiter, the waiter received a fraction of 8 / 13 of the total number of slices, which totals 8 / 13 * 78 = 48 slices. Twenty less the number of slices of pizza that the waiter ate is 48 - 20 = 28. The answer is 28.