If '+' means '−', '−' means '+', '×' means '÷', then 50 + 10 − 5 × 5 = ?

Question

If '+' means '−', '−' means '+', '×' means '÷', then 50 + 10 − 5 × 5 = ?

1. A. 41 (Correct answer)
2. B. 60
3. C. 65
4. D. 70

Correct Answer

Option A — 41

Detailed Solution & Explanation

The correct answer is 41.

Key Points

• Substitute as instructed: + → −, − → +, × → ÷.
• The expression 50 + 10 − 5 × 5 becomes 50 − 10 + 5 ÷ 5.
• Apply BODMAS: division first, 5 ÷ 5 = 1.
• Then left to right: 50 − 10 = 40, and 40 + 1 = 41.

Additional Information

• Only three symbols are reassigned here, and division is the one that must be resolved before the additions and subtractions — evaluating strictly left to right without applying precedence gives 45 and misses the answer.
• The swap is mutual between + and −, so every occurrence of each must be changed; changing one and overlooking the other is a frequent slip.
• Write out the fully converted expression before calculating. In questions where several symbols are reassigned, the transcription step is where marks are won or lost, not the arithmetic.

प्रश्न (हिन्दी में)

यदि '+' का अर्थ '−' है, '−' का अर्थ '+' है, '×' का अर्थ '÷' है, तो 50 + 10 − 5 × 5 = ?

1. A. 41
2. B. 60
3. C. 65
4. D. 70