Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
IAT IISER2026MathematicsBinomial Theorem

Let n = 20²⁶ . What is the remainder when 49^n + 41^n + 10n is divided by 100?

Options

  1. A1
  2. B49
  3. C90
  4. D2

Correct answer

D. 2

Step-by-step solution

Given n = 20²⁶ . We need to find the remainder when 49^n + 41^n + 10n is divided by 100 . First, analyze the value of n modulo 100 : n = 20²⁶ = (20^2)¹³ = 400¹³ . Since 400 is a multiple of 100 , 400¹³ 0 100 . Thus, n 0 100 . This implies 10n 0 100 . Next, evaluate 49^n 100 : 49^n = (50 - 1)^n = ^ n C₀ 50^n - ^ n C₁ 50^ n-1 + - ^ n C_ n-1 50 + ^ n C_ n (-1)^n . Since n = 20²⁶ is an even integer, (-1)^n = 1 . Also, n is a multiple of 100 , so n = 100k for some integer k . The term ^ n C_ n-1 50 = 50n = 50(100k) = 50

Practice Binomial Theorem on Quantrex Academy →

More from Binomial Theorem

If n 13 , n 14 and n 15 are in arithmetic progression, then the positive integer value of ' n ' can be 2026If the coefficients of x^2 and x^3 in the expansion of (3 + kx)^9 are equal, then the value of ' k ' is 2026The remainder when 7¹⁰³ is divided by 25 is 2026_ r=1 ¹⁵ r^2 ( ¹⁵ C_r 15 r-1 )= 20251 81^ n - ^ 2 n C ₁ 10 81^ n + ^ 2 n C ₂ 10^2 81^ n - + 10^ 2 n 81^ n = 2025If x is positive real number and the first negative term in the expansion of (1+ x )^ 27 / 5 is t _ k then k = 2025In the binomial expansion of (p-q)¹⁴ , if the sum of 7^ th term and 8^ th term is zero, then p+q p-q = 2025The numerically greatest term in the expansion of (x+3 y)¹³ , when x= 1 2 and y= 1 3 is 2025 Full Binomial Theorem list All IAT IISER PYQs