Question: Matias is a salesman in a bookstore. He sold 7 books on Tuesday and three times as many on Wednesday. If the sales from Wednesday were tripled on Thursday, how many books did Matias sell during these three days combined?
Answer with step-by-step thinking: Matias sold 7 * 3 = 21 books on Wednesday, as he sold three times more books than on Tuesday. The sales from Wednesday were tripled on Thursday, which means Matias sold then 21 * 3 = 63 books. That means in total Matias sold 7 + 21 + 63 = 91 books during these three days.
So the answer is 91.


Question: Alexander was 50 inches on his 8th birthday. If he grows 1/2 a foot a year, how many inches tall will he be on his 12th birthday?
Answer with step-by-step thinking: He grows six inches a year because 12 x .5 = 6. He will grow 24 inches between his 8th and 12th birthday because 4 x 6 = 24. He will be 74 inches tall because 50 + 24 = 74.
So the answer is 74.


Question: Erin is watching a TV mini series of Pride and Prejudice. There are 6 episodes that are each 50 minutes long. If Erin watches all of the episodes in one sitting, one after the other with no breaks, how many hours will she spend watching the series?
Answer with step-by-step thinking:
The total minutes in the series is 6 * 50 = 300 minutes. Since there are 60 minutes in an hour, Erin will spend 300 / 60 = 5 hours watching the series.
So the answer is 5.