Question

Which two signs should be interchanged to make the given equation correct?

97 × 23 - 18 + 9 ÷ 3 = 66

• A. + and -
• B. × and ÷
• C. × and +
• D. ÷ and -

Answer 1

Answer:

C. × and +

Solution:

BODMAS Rule:

Lets check each option:

1) + and -

After interchanging signs, we get:

⇒ 97 × 23 +18 - 9 ÷ 3

⇒ 97 × 23 + 18 - 3

⇒ 2231 + 23 - 3

⇒ 2254 - 3

⇒ 2251 ≠ 66

 

2) × and ÷

After interchanging signs, we get:

⇒ 97 ÷ 23 - 18 + 9 × 3

⇒ 4.217 - 18 + 9 × 3

⇒ 4.217 - 18 + 27

⇒ 4.217 - 45

⇒ 40.783 ≠ 66

 

3) × and +

After interchanging signs, we get:

⇒97 + 23 - 18 × 9 ÷ 3

⇒ 97 + 23 - 18 × 3

⇒ 97 + 23 - 54

⇒ 120 - 54 

⇒ 66 = 66

 

4) ÷ and -

After interchanging signs, we get:

⇒97 × 23 ÷ 18 + 9 - 3

⇒ 97 × 1.27 + 9 - 3

⇒ 123.94 + 9 - 3

⇒ 132.94 - 3

⇒ 129.94 ≠ 66

Hence, 'option C' is the correct answer.