If ‘+’ stands for ‘\(\div\)’, ‘\(\div\)’ stands for ‘\(\times\)’, ‘\(\times\)’ stands for ‘−’ and ‘−’ stands for ‘+’, which one of the following is correct?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → \(18+6\div 7\times 5-2=18\)
Replace every sign by the one it stands for (+ by \(\div\), \(\div\) by \(\times\), \(\times\) by −, − by +), then work out the left side by BODMAS (division and multiplication before addition and subtraction).
Option (1) becomes \(18\times6-7\div5+2=108-1.4+2=108.6\), not 22
Option (2) becomes \(\displaystyle 18-6\div7\times5+2=20-\frac{30}{7}=15\frac{5}{7}\), not 16
Option (3) becomes \(18\times6+7\div5-2=108+1.4-2=107.4\), not 20
Option (4) becomes \(18\div6\times7-5+2=21-5+2=18\), which is true