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(i) ""^(50)C(47)= ………. (ii) ""^(15...

(i) `""^(50)C_(47)=` ……….
(ii) `""^(15)C_(14)=` ………….

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To solve the given problems, we will use the formula for combinations, which is: \[ ^nC_r = \frac{n!}{r!(n-r)!} \] ### Part (i): Calculate \( ^{50}C_{47} \) 1. **Identify n and r**: Here, \( n = 50 \) and \( r = 47 \). 2. **Use the formula**: \[ ^{50}C_{47} = \frac{50!}{47!(50-47)!} = \frac{50!}{47! \cdot 3!} \] 3. **Simplify the factorials**: \[ 50! = 50 \times 49 \times 48 \times 47! \] Therefore, we can write: \[ ^{50}C_{47} = \frac{50 \times 49 \times 48 \times 47!}{47! \cdot 3!} \] 4. **Cancel out \( 47! \)**: \[ ^{50}C_{47} = \frac{50 \times 49 \times 48}{3!} \] 5. **Calculate \( 3! \)**: \[ 3! = 3 \times 2 \times 1 = 6 \] 6. **Substitute back**: \[ ^{50}C_{47} = \frac{50 \times 49 \times 48}{6} \] 7. **Perform the multiplication**: \[ 50 \times 49 = 2450 \] \[ 2450 \times 48 = 117600 \] 8. **Divide by 6**: \[ ^{50}C_{47} = \frac{117600}{6} = 19600 \] ### Part (ii): Calculate \( ^{15}C_{14} \) 1. **Identify n and r**: Here, \( n = 15 \) and \( r = 14 \). 2. **Use the formula**: \[ ^{15}C_{14} = \frac{15!}{14!(15-14)!} = \frac{15!}{14! \cdot 1!} \] 3. **Simplify the factorials**: \[ 15! = 15 \times 14! \] Therefore, we can write: \[ ^{15}C_{14} = \frac{15 \times 14!}{14! \cdot 1!} \] 4. **Cancel out \( 14! \)**: \[ ^{15}C_{14} = \frac{15}{1!} \] 5. **Calculate \( 1! \)**: \[ 1! = 1 \] 6. **Substitute back**: \[ ^{15}C_{14} = \frac{15}{1} = 15 \] ### Final Answers: - \( ^{50}C_{47} = 19600 \) - \( ^{15}C_{14} = 15 \)
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