Which two numbers should be interchanged to make the given equation correct?
17 × 7 + (21 ÷ 3) × 5 – 28 + 34 = 72
(NOTE: Numbers must be interchanged and not the constituent digits e.g. if 2 and 3 are to be interchanged in the equation 43 × 3 + 4 ÷ 2, then interchanged equation is 43 × 2 + 4 ÷ 3)
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 7 and 3
Given equation: 17 × 7 + (21 ÷ 3) × 5 – 28 + 34 = 72
Option 1) 7 and 3
17 × 3 + (21 ÷ 7) × 5 – 28 + 34 = 72
17 × 3 + 3 × 5 – 28 + 34 = 72
51 + 15 - 28 + 34 = 72
100 - 28 = 72
72 = 72