Match List-I with List-II
|
List-I |
List-II |
|
(A) ${^{75}P}_2-{^{75}C}_2$ |
(I) 504 |
|
(B) ${^5P}_5-{^{10}C}_3$ |
(II) 6 |
|
(C) ${^{16}C}_{13}-{^8C}_3$ |
(III) 2775 |
|
(D) ${^nP}_4=360$, then find $n$ |
(IV) 0 |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → (A)-(III), (B)-(IV), (C)-(I), (D)-(II)
|
List-I |
List-II |
|
(A) ${^{75}P}_2-{^{75}C}_2$ |
(III) 2775 |
|
(B) ${^5P}_5-{^{10}C}_3$ |
(IV) 0 |
|
(C) ${^{16}C}_{13}-{^8C}_3$ |
(I) 504 |
|
(D) ${^nP}_4=360$, then find $n$ |
(II) 6 |
(A) $^{75}P_2 - ^{75}C_2$
- $^{75}P_2 = 75 \times 74 = 5550$
- $^{75}C_2 = \frac{75 \times 74}{2 \times 1} = 2775$
- Difference: $5550 - 2775 = \mathbf{2775}$
- Matches: (III)
(B) $^5P_5 - ^{10}C_3$
- $^5P_5 = 5! = 120$
- $^{10}C_3 = \frac{10 \times 9 \times 8}{3 \times 2 \times 1} = 120$
- Difference: $120 - 120 = \mathbf{0}$
- Matches: (IV)
(C) $^{16}C_{13} - ^8C_3$
- $^{16}C_{13} = ^{16}C_{16-13} = ^{16}C_3 = \frac{16 \times 15 \times 14}{3 \times 2 \times 1} = 560$
- $^8C_3 = \frac{8 \times 7 \times 6}{3 \times 2 \times 1} = 56$
- Difference: $560 - 56 = \mathbf{504}$
- Matches: (I)
(D) $^nP_4 = 360$
- We need to find $n$ such that $n(n-1)(n-2)(n-3) = 360$.
- Testing $n = 6$: $6 \times 5 \times 4 \times 3 = 360$.
- Matches: (II)