If 1 + 4 = 9, 2 + 8 = 18, 3 + 6 = 15 then 7 + 8 = ?
2023
If 1 + 4 = 9, 2 + 8 = 18, 3 + 6 = 15 then 7 + 8 = ?
- A.
41
- B.
23
- C.
30
- D.
32
Attempted by 40 students.
Show answer & explanation
Correct answer: B
Identify the pattern: each result equals the first number plus twice the second number.
Check with 1 and 4: 1 + 2×4 = 1 + 8 = 9 (matches).
Check with 2 and 8: 2 + 2×8 = 2 + 16 = 18 (matches).
Check with 3 and 6: 3 + 2×6 = 3 + 12 = 15 (matches).
Apply the rule to 7 and 8:
Compute twice the second number: 2 × 8 = 16.
Add the first number: 7 + 16 = 23.
Answer: 23