SSC CHSL 2022 PYQ — Question 54

The correct answer is option 1 i.e.  $4096\dfrac{1}{512}$.

Given:

r + 64/r = 16

Calculations:

According to the question;

⇒ r² + 64 = 16r

⇒ r² - 8r - 8r + 64 = 0

⇒ (r - 8) (r - 8) = 0

⇒ r = 8

Put the value of r = 8, we get

⇒ r⁴ + (1/r³) = (8)⁴ + (1/8)³

⇒ 4096 + (1/512)

⇒ $4096\dfrac{1}{512}$