By interchanging the two numbers 20 and 36, which of the following equations will be correct?
I. 55 +42 − 36 × 20 ÷ 9 = 17
II. 20 ÷ 2 × 36 + 81 − 41 = 400
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e Both I and II
The given equations are:
I. 55 +42 − 36 × 20 ÷ 9 = 17
II. 20 ÷ 2 × 36 + 81 − 41 = 400
By interchanging 20 and 36, the equations will be:
I. 55 +42 − 20 × 36 ÷ 9 = 17
55 +42 − 20 × 4 = 17
55 +42 − 80 = 17
17 = 17
The equation is balanced.
II. 36 ÷ 2 × 20 + 81 − 41 = 400
18 × 20 + 81 − 41 = 400
360 + 81 − 41 = 400
400 = 400
The equation is balanced.
Both equation I and II are balanced.
Hence, option 3 is the correct option.