What approximate value should come in the place of question mark (?) in the following question? 

[(36.01)² – (24.99)²]/? = (8.99)2 – (4.01)2

Rules of Approximation:

1. If a  number has digits to the right of the decimal less than 5, then just drop the digits to the right of the decimal. The number so obtained will be the approximated value.

2. If a number has digits to the right of the decimal more than 5, then just drop the digits to the right of the decimal and raise the remaining number by '1'.The number so obtained will be the approximated value.

Concept:

Follow BODMAS rule to solve this question, as per the order given below, 

Step - 1: Parts of an equation enclosed in 'Brackets' must be solved first, and following BODMAS rule in the bracket,

Step - 2: Any mathematical 'Of' or 'Exponent' must be solved next.

Step - 3: Next, the parts of the equation that contain 'Division' and 'Multiplication' are calculated.

Step - 4: Last but not least, the parts of the equation that contain 'Addition' and 'Subtraction' should be calculated.

Since we need to find out the approximate value, we can write these values to their nearest integers.

Calculation:

Given expression is

[(36)2 – (25)2]/? = (9)2 – (4)2

⇒ [362 – 252]/? = 92 – 42

⇒ [(36 + 25) × (36 – 25)] /? = (9 + 4) × (9 – 4)

⇒ [(61) × (11)] /? = (13) × (5)

⇒ 671/? = 65

⇒ 671/65 =?

⇒ 10.32 =?

⇒ 10 ≈ ?