Identify the missing number.
13 34 50 ? 91 62 25 100
Answer: A
Explanation: The numbers on the left add up to 200. The answer must be 25 to make the numbers on the right add up to 200.
7 12 12 17 22 17 ? 22
Answer: E
Explanation: The numbers on the right are (n + 5) where n is the number in the corresponding position on the left. Therefore the answer must be (22 + 5) = 27.
Identify the missing number or letter within the series.
Q, S, ?, Z
ANswer: C
Explanation : The interval between letters increases by 1 each time, so V is the third in the series.
?, 125, 64, 27, 8, 1
Answer: D
Explanation: The numbers in this series are descending cubes of 6,5,4,3,2,1
21, ?, 8, 5, 3, 2
Answer: C
Explanation: Subtract each number from the previous one to get the next in the series. For example, 8-5=3, 5-3=2, etc. The second number in the series is 13 since 21-13 = 8.
