Question

$^nP_5=42^nP_3$ n ന്ടെ വിലയെത്ര ?

• A. 15
• B. 20
• C. 10
• D. 5

Answer 1

Answer:

C. 10

n(n-1)(n-2)(n-3)(n-4)=42 n(n-1)(n-2) (n-3)(n-4)=42 (10-3)(10-4)= 7 x 6 = 42 n=10