Question

(78 - 28) + 25 $÷$ 14 $\times$ 7 = 100

• A. - $\times$
• B. $\times ÷$
• C. $÷-$
• D. + -

Answer 1

The correct option is B $\times ÷$

The given equation is: (78 - 28) + 25 $÷$ 14 $\times$ 7 = 100
(1) After interchanging - and $\times$, the new equation is:
$78\times 28+25÷14-7=2184+51.78-7=2228.78$
Hence, $LHS\ne RHS$
(2) After interchanging $\times$ and $÷$, the new equation is:
$(78-28)+25\times 14÷7=100$
LHS: $(78-28)+25\times 14÷7=50+50=100$
Hence, LHS = RHS.