If the signs are interchanged as follows: • ‘+’ means ‘×’ • ‘−’ means ‘÷’ • ‘×’ means ‘+’ • ‘÷’ means ‘−’ Choose the correct equation from the options below.

Correct — A.
Rule: rewrite each option with the true signs (+ → ×, − → ÷, × → +, ÷ → −), then check both sides.

Option (a): 8×4÷5 becomes 8 + 4 − 5
8 + 4 = 12
12 − 5 = 7, which matches the right side → option (a).

Why the others are wrong

• (b)
  12+3−6=10 — 12+3−6 becomes 12 × 3 ÷ 6 = 36 ÷ 6 = 6. The right side says 10, so the equation is false.
• (c)
  18÷6+3=5 — 18÷6+3 becomes 18 − 6 × 3 = 18 − 18 = 0, not 5. The multiplication is done before the subtraction.
• (d)
  7−2+3=12 — 7−2+3 becomes 7 ÷ 2 × 3 = 3.5 × 3 = 10.5, not 12.

When the stem says '+' means '×', every + printed in the options is really a multiplication. The printed sign is a label; the rule tells you what it stands for.

Convert the whole left side first, then apply BODMAS to the converted expression. With only two operations per option, checking all four is quick.

Here the rule is two swaps: + and × trade places, and so do − and ÷.

Key facts

• Under this rule + and × trade meanings, and so do − and ÷.
• Converted, the four left sides come to 7, 6, 0 and 10.5, against right sides of 7, 10, 5 and 12.

Common traps

• Converting the signs and then working left to right: 18 − 6 × 3 read that way gives 36 instead of 0.
• Reading 7 ÷ 2 × 3 as 7 ÷ 6. Division and multiplication share a priority and run left to right, giving 10.5.

No directly related past PYQ was found.