Question: Djibo is 17 years old. Five years ago Djibo added his age with his sister's age and the sum was 35. How many years old is Djibo's sister today?
Answer: Age 5 years ago: 17 - 5 = 12. Sister's age 5 years ago: 35 - 12 = 23. Sister's age today: 23 + 5 = 28 years. Djibo's sister is 28 years old today. The answer is 28.

Question: Jerome is taking a 150-mile bicycle trip. He wants to ride 12 miles for 12 days. How long will he ride on the 13th day to finish his goal?
Answer: Jerome rides a total of 12 x 12 = 144 miles in 12 days. So, he will ride 150 - 144 = 6 miles on the 13th day to finish his goal. The answer is 6.

Question: Jill spends time every day talking to her boyfriend on the phone. The first day of the week she spends 5 minutes on the phone with her boyfriend. Each of the following days she spends twice as much time talking on the phone as the day before. After the 5th day her parents take the phone away from her because she was on it too long. How much time did Jill spend talking to her boyfriend that week?
Answer: Jill starts off spending 5 minutes on the phone, and the following day she spends double that 5 minutes for 5 * 2 = 10 minutes. The following day Jill spends double the previous day's total of 10 minutes on the phone, for 10 * 2 = 20 minutes. On the fourth day, Jill spends double the previous day's total of 20 minutes on the phone, for 20 * 2 = 40 minutes. On the fifth and final day, Jill spends double the previous day's total of 40 minutes on the phone, for 40 * 2 = 80 minutes. All told, Jill spends 5 + 10 + 20 + 40 + 80 = 155 minutes on the phone over 5 days. The answer is 155.

Question: A chef has served 58 adults, 35 fewer children than the number of adults, and twice as many seniors as children. What is the total number of guests served?
Answer:
The chef has served 58 - 35 = 23 children. The chef has served 23 x 2 = 46 seniors. Therefore, the total number of guests that the chef has served is 58 + 23 + 46 = 127. The answer is 127.