Question

The kinder garden teacher has $25$ kids in her class. She takes $5$ of them at a time, to zoological garden as often as she can, without taking the same $5$ kids more than once. Then the number of visits, the teacher makes to the garden exceeds that of a kid by?

• A. ${}^{25}{C}_5-{}^{24}{C}_5$
• B. ${}^{24}{C}_5$
• C. ${}^{24}{C}_4$
• D. None

Answer 1

Answer: (B)

${}^{24}{C}_5$

The number of times the kids made to the zoological garden ${}^{25}{C}_5$

The number of times a kid is not made to the garden ${}^{24}{C}_5$

Therefore the number of times a kid made to garden ${=}^{25}{C}_5{-}^{24}{C}_5$

$=53130-42504=10626$

Therefore the number of visits ${=}^{25}{C}_5-10626{=}^{24}{C}_5$