4. Probability

Counting

4. Probability

Counting

Struggling with Statistics?

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Multiple Choice

Emily is organizing her closet. She has 15 shirts left to hang but has space in one section for 6 shirts. How many ways could she hang shirts in that section?

$3,603,600$

$90$

$9$

$362,880$

Verified step by step guidance

Identify the problem as a permutation problem where Emily needs to select and arrange 6 shirts out of 15.

Use the permutation formula, which is given by:

P (n, r) = \frac{n!}{(n - r)!}

, where

n

is the total number of items to choose from, and

r

is the number of items to arrange.

Substitute the values into the formula:

P (15, 6) = \frac{15!}{(15 - 6)!}

Calculate

15!

and

9!

separately. Factorial is the product of all positive integers up to that number.

Divide

15!

9!

to find the number of permutations, which will give you the number of ways Emily can hang the shirts.

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Textbook Question

4. The table on the left shows the secondary school student enrollment levels (in thousands by grade) in Oklahoma and Texas schools in a recent year. (Source: U.S. Nation

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Textbook Question

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b. Presentation subjects are based on the units of the course. Unit B is covered by three students, Unit C is covered by five students, and Units A and D are each covered by four students. How many presentation orders are possible when presentations on

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Multiple Choice

A student formed a club at their school. They have 13 members, and need to elect a president, vice president, and treasurer. How many ways are there to fill these officer positions?

Evaluate the given expression. $_9P_4$

You want to arrange the books on your bookshelf by color. How many different ways could you arrange 12 books if 4 of them have a blue cover, 3 are yellow, and 5 are white?

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140