**Question:**

If the number of 5 -element subsets of the set $A=\left\{a_{1}, a_{2}, \ldots ., a_{20}\right\}$ of 20 distinct elements is $k$ times the number of 5-element subsets containing $a_{4}$, then $k$ is

Correct Option: 3

JEE Main Previous Year Online May 7, 2012

**Solution:**