Question

5, 7, 8, 10, 12, 14, 17, 19, ____

• A. 21
• B. 20
• C. 22
• D. 23

Answer 1

Answer:

D. 23

The next number in the series is 23.

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This sequence is made by combining two separate alternating series:

• First Series (Odd positions: 1st, 3rd, 5th, 7th, 9th numbers):

  • 5, 8, 12, 17, ?

  • The difference between numbers increases by 1 each time (+3, +4, +5, +6):

    • $5 + 3 = 8$

    • $8 + 4 = 12$

    • $12 + 5 = 17$

    • $17 + 6 = \mathbf{23}$

• Second Series (Even positions: 2nd, 4th, 6th, 8th numbers):

  • 7, 10, 14, 19

  • This follows the exact same growing pattern (+3, +4, +5):

    • $7 + 3 = 10$

    • $10 + 4 = 14$

    • $14 + 5 = 19$

Since the missing blank falls on the 9th position (belonging to the first series), the final answer is 23.