Riddles
I am a number. Double me, subtract 17, then add 6. The answer is 41. What am I?
26
4, 9, 19, 39, 79, ___, ___, ___
Answer: 159, 319, 639
Explanation: Multiply each number by 2, then add 1.
8 11/18 − 3 7/12
4 37/36 = 5 1/36
The temperature was −8°F in the morning. By noon, it increased 15°F, then dropped 12°F overnight. What was the final temperature?
Answer: −5°F
9,384 ÷ 24
Answer: 391
I am a number. Triple me, add 12, then divide by 6. The answer is 11. What am I?
18
5, 8, 14, 26, 50, ___, ___, ___
Answer: 98, 194, 386
Explanation: Multiply each number by 2, then subtract 2.
5 13/20 + 4 17/30
10 13/60
A runner completed 2 3/4 miles on Monday and 3 5/8 miles on Tuesday. She wanted to run 8 miles total. How many more miles did she need to run?
1 5/8 miles
6,864 ÷ 24
286
I am a two-digit number. My digits add to 14, and my tens digit is 4 more than my ones digit. What number am I?
95
3, 10, 31, 94, 283, ___, ___, ___
Answer: 850, 2551, 7654
Explanation: Multiply by 3, then add 1 each time.
14 19/24 − 6 11/16
8 5/48
A tank contained 15 1/2 gallons of water. 4 3/4 gallons were drained, and then 2 5/8 gallons were added back. How much water is in the tank now?
Answer: 13 3/8 gallons
9,575 ÷ 25
383
I am an even number. Divide me by 8, then add 9. The answer is 23. What number am I?
112
4, 14, 44, 134, 404, ___, ___, ___
Answer: 1214, 3644, 10934
Explanation: Multiply by 3, then add 2 each time.
9 17/28 + 7 19/42
17 5/84
A water tank held 18 3/4 gallons. During the day, 6 5/8 gallons were used, and then 4 7/12 gallons were added back. How much water is in the tank now?
16 17/24 gallons
14,587 ÷ 36
Answer: 405 R7
I am a negative integer. When you square me, then subtract 44, the answer is 100. What number am I?
-12
6, 25, 102, 411, 1648, ___, ___, ___
Answer: 6597, 26394, 105579
Explanation: Multiply by 4, then add 1 each time.
16 17/24 − 8 13/20
8 7/120
A submarine started at −135 feet below sea level. It rose 48 1/2 feet, then descended 72 3/4 feet, and finally rose 39 1/4 feet. What was the submarine's final depth?
−120 feet
45,638 ÷ 57
Answer: 800 R38