Q: A library has a collection of 100 historical novels arranged on a shelf. 5 people borrow 2 books each from the shelf on a particular day, and 20 more books are borrowed from the shelf on the second day. How many books are remaining on the shelf after the second day?
A: 70
Step-by-step reasoning process: Five people borrowed 5 people * 2 books / person = 10 books on the first day. After the second day, the total number of borrowed books increased to 10 books + 20 books = 30 books. The total number of books on the shelf after the second day is 100 books - 30 books = 70 books.


Q: A four-layer pyramid is being built with each layer having three times as many sandstone blocks as the layer above it. The top layer is a single block. How many sandstone blocks are in the pyramid?
A: 40
Step-by-step reasoning process: There are 1 * 3 = 3 blocks in the second layer. There are 3 * 3 = 9 blocks in the third layer. There are 9 * 3 = 27 blocks in the fourth layer. Thus, there are 1 + 3 + 9 + 27 = 40 sandstone blocks in the pyramid.


Q: Alex and his friend had a free throw contest. Alex made 8 baskets. Sandra made three times as many baskets as Alex and Hector made two times the number of baskets that Sandra made. How many baskets did they make in total?
A: 80
Step-by-step reasoning process: Sandra made 3 * 8 = 24 baskets. Hector made 24 * 2 = 48 baskets. In total they made 8 + 24 + 48 = 80 baskets.


Q: Jenny had $24 left after spending 3/7 of her money. How much is half of her original amount of money?
A: 21
Step-by-step reasoning process: Jenny spent 1 - 3 / 7 = 4 / 7 of her money. Since 4 / 7 is equal to $24, then 1 / 7 is equal to $24 / 4 = $6. So, Jenny originally had $6 x 7 = $42. Therefore, half of her original amount of money is $42 / 2 = $21.