Question

Use the Counting Principle to find the probability. Choosing the 7 winning lottery numbers when the numbers are chosen at random from 0 to 9

Answer 1

Answer:   120

Step-by-step explanation:

Since the order of the numbers doesn't matter we can use the formula:

$\dfrac{n!}{r!(n-r)!}\quad \text{where n is the quantity of items and r is the quantity chosen}\\\\\text{In this problem, there are 10 numbers (n = 10) and 7 to be chosen (r = 7)}\\\\_{10}C_{7}=\dfrac{10!}{7!(10-7)!}\\\\.\qquad=\dfrac{10!}{7!3!}\\\\.\qquad=\dfrac{10\times 9\times 8\times 7!}{7!\times 3\times 2\times 1}\\\\.\qquad=10\times 3\times 4\\\\.\qquad=120$

Answer 2

Answer:

1/10,000,000  (gradpoint)

Step-by-step explanation: