Question

( begin{aligned} text { No. of conbination } &={ }^{7} C_{1} &=frac{7 !}{1 ! 6 !}=frac{7 times 6 !}{6 !} &=7 frac{1 !}{4 cdot operatorname{Ars}} end{aligned} )

# 5. A student can enter "TRINITY' college by 7 different gates and allowed to return by the gate which is used to enter the earlier. on how many ways he can complete his journey. B) 42 C) 6 D) 1

Solution