Question

in a school there are four sections of 40 students each in 11th standard in how many ways can a set of 4 student representatives be chosen one from each section

Answer 1

We can choose 1 student from 40 students in ⁴°C₁ ways.

So a set of 4 students can be chosen in = ⁴°C₁×⁴°C₁×⁴°C₁×⁴°C₁ ways

⁴°C₁ = 40!/(1!×39!) = 40

So total number of ways = 40×40×40×40 = 2560000