Number Series Flashcards

Think about the subsequent series: 23, …, 31, 37. What number is missing?

Answer: 29

The sequence 23, ..., 31, 37 consists of prime numbers. A prime number is a natural number greater than 1 that has no positive divisors other than 1 and itself. The prime number that comes directly after 23 and before 31 is 29. Therefore, 29 is the missing number in the sequence.

Think about sequences 26, 24, 20, and 14. What figure should come after that?

Answer: 6

Analyze the differences between consecutive numbers: 26 - 24 = 2, 24 - 20 = 4, 20 - 14 = 6. The differences are increasing by 2 each time (2, 4, 6). Following this pattern, the next difference should be 8. Subtracting 8 from the last number in the sequence gives 14 - 8 = 6. So, 6 is the next figure.

Think about the sequences 5, 6, 11, and 17. What figure should come after that?

Answer: 28

This sequence follows a pattern similar to the Fibonacci sequence, where each number is the sum of the two preceding numbers. Starting with 5 and 6: 5 + 6 = 11, and 6 + 11 = 17. Following this rule, the next number in the sequence will be the sum of the last two numbers: 11 + 17 = 28. Therefore, 28 is the next figure.

Think about sequences 3, 6, 11, and 18. What figure should come after that?

Answer: 27

Examine the differences between consecutive numbers: 6 - 3 = 3, 11 - 6 = 5, 18 - 11 = 7. The differences are consecutive odd numbers (3, 5, 7). Following this pattern, the next difference should be 9. Adding 9 to the last number in the sequence gives 18 + 9 = 27. So, 27 is the next figure.

Think about the sequences 6, 12, 24, and 48. What figure should come after that?

Answer: 96

This is a geometric sequence where each number is obtained by multiplying the previous number by 2. Starting with 6: 6 * 2 = 12, 12 * 2 = 24, and 24 * 2 = 48. Following this pattern, the next number in the sequence will be 48 * 2 = 96. Therefore, 96 is the next figure.

Think about the subsequent series: 26, 21, …, 11, 6. What number is missing?

Answer: 16

Observe the differences between the given numbers: 26 - 21 = 5, and 11 - 6 = 5. This indicates a consistent pattern where each number is 5 less than the previous one. To find the missing number, subtract 5 from 21: 21 - 5 = 16. The sequence is 26, 21, 16, 11, 6.

Think about sequences 25, 33, 41, and 49. What figure should come after that?

Answer: 57

Examine the differences between consecutive numbers: 33 - 25 = 8, 41 - 33 = 8, 49 - 41 = 8. The pattern shows that each number is obtained by adding 8 to the previous number. Following this consistent pattern, the next number in the sequence will be 49 + 8 = 57. Therefore, 57 is the next figure.