Janice had X sentences from yesterday already typed to start with today. Janice typed 6 * 20 = 120 sentences before her break. She typed 6 * 15 = 90 sentences after her break. She typed 6 * 18 = 108 sentences after her meeting. Therefore, she typed 120 + 90 + 108 = 318 sentences today in all. She had to erase 40 sentences, so she had 318 - 40 = 278 sentences that she typed today left. The paper had X + 278 = 536 sentences at the end of today. Thus, she had X = 536 - 278 = 258 sentences typed on the paper to start with today.
The answer: 258
Reverse engineering the question: Janice can type 6 sentences per minute. Today at work, Janice continued working on a paper she started typing yesterday. She typed for 20 minutes, took a break, and typed 15 minutes longer. She then had to erase 40 sentences she had typed incorrectly. After a meeting, she typed for 18 minutes more. In all, the paper had 536 sentences by the end of today. How many sentences did she start with today?

Sandra made 3 * 8 = 24 baskets. Hector made 24 * 2 = 48 baskets. In total they made 8 + 24 + 48 = 80 baskets.
The answer: 80
Reverse engineering the question: 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?

Let's first calculate the total number of cookies: 25 X 3 = 75 cookies. Let us now share these cookies among the 5 children: 75 / 5 = 15 cookies.
The answer: 15
Reverse engineering the question: For his birthday, Aku invited 4 friends. His mother bought 3 packages of cookies each containing 25 cookies. After playing football, the children came to eat and celebrate Aku's 10th birthday, each eating an equal number of all the cookies. Calculate the number of cookies that each child will eat.

Knowing Kevin's record of eating 70 wings in 8 minutes or 64 / 8 = 8 wings in a minute. Alan must increase his ability to eat 5 wings per minute to 8 - 5 = 3 wings per minute to equal Kevin's world record. To beat Kevin, Alan must eat 3 + 1 = 4 hot wings per minute.
The answer: 4
Reverse engineering the question:
Kevin holds the world record for eating the biggest quantity of hot wings in 8 minutes. He can eat 64 wings without stopping. Alan, a boy who loves hot wings, wants to beat Kevin's record. He is currently able to eat 5 hot wings per minute. How many more wings must he eat per minute to beat Kevin's record?