In how many ways 2 students can be chosen from the class of 20 students?
A. 190
B. 180
C. 240
D. 390
Answer: Option A
Solution (By Examveda Team)
Number of ways$$\eqalign{ & { = ^{20}}{{\text{C}}_2} \cr & = \frac{{20!}}{{2! \times 18!}} \cr & = 20 \times \frac{{19}}{2} \cr & = 190 \cr} $$
This Question Belongs to Arithmetic Ability >> Permutation And Combination
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