CAT 2021 Question Paper | Quant Slot 2

CAT 2021 Quant was dominated by Arithmetic followed by Algebra. In Arithmetic, the questions were dominated by topics like Speed-time-distance, Mixture and Alligations. This year, there was a surprise. The questions from Geometry were relatively on the lower side as compared to the previous years. There were 8 TITA Qs this year. Overall this section was at a medium level of difficulty.

Question 2 : If log₂[3 + log₃{4 + log₄(x - 1)}] - 2 = 0 then 4x equals

Video Explanation

Explanatory Answer

log₂[3+log₃{4+log₄(x-1)}]- 2= 0
log₂[3 + log₃{4 + log₄(x - 1)}] = 2
3 + log₃{4 + log₄(x - 1)} = 4 ( ∵ log_aN = x ⇒ N = a^x )
log₃{4 + log₄(x - 1)} = 1
4 + log₄(x - 1) = 3
log₄(x - 1) = -1
x - 1 = \\frac{1}{4})
4x = 5

The question is " If log₂[3 + log₃{4 + log₄(x - 1)}] - 2 = 0 then 4x equals "

Hence, the answer is '5'