Math Problem Statement

(24 choose 7)

Solution

The binomial coefficient (247)\binom{24}{7}, also known as "24 choose 7", is calculated using the formula:

(nr)=n!r!(nr)!\binom{n}{r} = \frac{n!}{r!(n - r)!}

Where:

  • n=24n = 24
  • r=7r = 7

Plugging the values into the formula:

(247)=24!7!(247)!=24!7!17!\binom{24}{7} = \frac{24!}{7!(24 - 7)!} = \frac{24!}{7!17!}

This simplifies to:

(247)=24×23×22×21×20×19×187×6×5×4×3×2×1\binom{24}{7} = \frac{24 \times 23 \times 22 \times 21 \times 20 \times 19 \times 18}{7 \times 6 \times 5 \times 4 \times 3 \times 2 \times 1}

Let's calculate the value:

(247)=24×23×22×21×20×19×185040\binom{24}{7} = \frac{24 \times 23 \times 22 \times 21 \times 20 \times 19 \times 18}{5040}

First, calculate the numerator:

24×23=55224 \times 23 = 552 552×22=12144552 \times 22 = 12144 12144×21=25502412144 \times 21 = 255024 255024×20=5100480255024 \times 20 = 5100480 5100480×19=969091205100480 \times 19 = 96909120 96909120×18=174433641696909120 \times 18 = 1744336416

Now, divide by the denominator:

17443364165040=345471\frac{1744336416}{5040} = 345471

Therefore, (247)=345471\binom{24}{7} = 345471.


Would you like more details or have any other questions on this?

Here are some related questions for you to explore:

  1. What is the formula for calculating combinations?
  2. How do binomial coefficients relate to Pascal's Triangle?
  3. What is the difference between permutations and combinations?
  4. How would you calculate (240)\binom{24}{0} or (2424)\binom{24}{24}?
  5. What is the significance of binomial coefficients in probability theory?

Tip: To simplify large factorials in binomial coefficient calculations, always cancel out terms that appear in both the numerator and the denominator.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Combinatorics
Binomial Coefficient
Factorials

Formulas

\( \binom{n}{r} = \frac{n!}{r!(n - r)!} \)

Theorems

Binomial Coefficient Formula

Suitable Grade Level

Grades 9-12