If (i). 84 ÷ 21 = 9 ; (ii). 56 ÷ 32 = 6 ; (iii). 37 ÷ 41 = 5

Question

If (i). 84 ÷ 21 = 9 ; (ii). 56 ÷ 32 = 6 ; (iii). 37 ÷ 41 = 5

The above operations are done using some logic.

Using same logic find number replaces '?' in the following:

87 ÷ 15 = ?

1. A. 0
2. B. 9 (Correct answer)
3. C. 7
4. D. 3

Correct Answer

Option B — 9

Detailed Solution & Explanation

The correct answer is 9.

Key Points

• Treat each two-digit number as a pair of digits, then compute (sum of the first number's digits) − (sum of the second number's digits).
• Check (i): 84 and 21 → (8 + 4) − (2 + 1) = 12 − 3 = 9 ✓
• Check (ii): 56 and 32 → (5 + 6) − (3 + 2) = 11 − 5 = 6 ✓
• Check (iii): 37 and 41 → (3 + 7) − (4 + 1) = 10 − 5 = 5 ✓
• Apply to 87 and 15: (8 + 7) − (1 + 5) = 15 − 6 = 9.

Additional Information

• The '÷' sign here is a decoy — the operation has nothing to do with division. Coded-operation questions routinely reuse familiar symbols for invented rules.
• Always validate a candidate rule against every worked example before applying it; a rule that fits two of three examples is the wrong rule.

*Ministry of Papers worked solution. The Commission has not yet published the official key for this paper; this answer will be reconciled with it on release.*