How do I solve this permutation 10P6/10P4 Answers A 420 B 30 C 5,040 D 151,200

How many ways can a dance instructor send 4 of her 11 students to a summer dance program?

Sedaia [141]

Answer:

d) 330

Step-by-step explanation:

The number of ways can a dance instructor send 4 of her 11 students to summer dance program is C(11 , 4)

That is $11_{C_{4} }$ ways

by using formula $n_{C_{r} } = \frac{n!}{(n-r)!r!}$

now simplification

$11_{C_{4} } = \frac{11!}{(11-4)!4!}$

= $\frac{11X10X9X8X7!}{(7!)4X3X2X1}$

after cancelling 7! and on simplification

= $\frac{11X10X9X8}{4X3X2X1}$

after cancellation we get 330 ways

The number of ways can a dance instructor send 4 of her 11 students to summer dance program is 330

8 0

3 years ago

Can someone please help me with this quiz or does anyone have the answer key it’s by Gina Wilson.

tatiyna

Answer:

put a more clear pic

Step-by-step explanation:

6 0

3 years ago

Find the value of x that will make A||B. 5x + 9 A B 6x-2 X = [?] Enter

givi [52]

Answer:

$x = 11$

Step-by-step explanation:

Given

Parallel lines A and B

Required

Find x

For A and B to be parallel, then 5x + 9 and 6x - 2 are alternate interior angles

And alternate interior angles are always equal

This means that

$5x + 9 = 6x - 2$

Collect like terms

$5x - 6x = -2 -9$

$-x = -11$

Multiply both sides by -1

$-1 * -x = -11 * -1$

$x = 11$

4 0

3 years ago

Read 2 more answers

A stalk of corn casts a shadow of 117 inches, while a 8-inch ear of corn casts a shadow of 13 inches. Use similar triangles to f

Gemiola [76]

Answer: 72

We can use ratios

117 inches / 13 inches = 9

The corn cast shadow is 9 times bigger than the example we are given.

9 * 8 = 72

7 0

1 year ago

Read 2 more answers

Help. Solving Multi Step Ratio Problems!

Romashka-Z-Leto [24]

Answer:

Part 1) $30\ coupons$

Part 2) $12\ sandwiches$

Part 3) $60\ push-ups$

Part 4) $96\ minutes$

Part 5) $\$95$

Part 6) $1\frac{7}{8}\ cups\ of\ pretzel$

Step-by-step explanation:

Part 1) we know that

At the Green House of Salad , you get a $1 coupon for every 3 salads you buy

so

Using proportion

Find out the number of salads you could buy to get $10 in coupons

$\frac{1}{3}=\frac{10}{x} \\\\x=3(10)\\\\x=30\ coupons$

Part 2) we know that

Kim orders catering for $35

She spend $5 on a large order of potato salad and the rest on turkey sandwiches

Each sandwich is $2.50

How many sandwiches does Kim buy?

step 1

Find out how many Kim spent on turkey sandwiches

Subtract $5 from $35

35-5=$30

step 2

Using proportion, find out the number of sandwiches

so

$\frac{1}{2.50}=\frac{x}{30}\\\\x=30/2.50\\\\x= 12\ sandwiches$

Part 3) we know that

Molly does 10 push-ups at the same time as Liza does 15 push-ups

so

Using proportion

Find out how many push-ups Liza does when Molly does 40 push-ups

$\frac{10}{15}=\frac{40}{x}\\\\x=15(40)/10\\\\x=60\ push-ups$

Part 4) we know that

A shark swim at a speed of 25 miles per hour

The shark rest after 40 miles

How long in minutes, does the shark swim before resting?

Using proportion

Find out how long in minutes the shark swim 40 miles

Remember that

$1\ h=60\ min$

$\frac{25}{60}\ \frac{miles}{minutes}=\frac{40}{x}\ \frac{miles}{minutes}\\\\x=60(40)/25\\\\x=96\ minutes$

Part 5) we know that

For every bar of soap that Aly sells, she earns $5

For every mug that Janet sells, she earns twice as much as Aly

Aly sells 5 bars of soap and Janet sells 7 mugs

How much money did they make altogether?

step 1

Find out the amount earned by Aly

using proportion

$\frac{1}{5}=\frac{5}{x}\\\\x=5(5)\\\\x=\$25$

step 2

Find out the amount earned by Janet

Remember that

For every mug that Janet sells, she earns twice as much as Aly

so

For every mug that Janet sells, she earns 2($5)=$10

using proportion

$\frac{1}{10}=\frac{7}{x}\\\\x=10(7)\\\\x=\$70$

step 3

Adds the amount earned by Aly plus the amount earned by Janet

$25+70=\$95$

Part 6) we know that

Ted is making trail mix for a party

He mixes 1 1/2 cups of nuts, 1/4 cup of rising and 1/4 cup of pretzel

How many cups of pretzel does Ted need to make 15 cups of trail mix?

Adds the quantities

$1\frac{1}{2}+\frac{1}{4} +\frac{1}{4}=2\ cups\ of \ trail\ mix$

That means

For every 2 cups of trail mix we need 1/4 cup of pretzel

using proportion

Find out how many cups of pretzel does Ted need to make 15 cups of trail mix

$\frac{2}{(1/4)}=\frac{15}{x}\\\\x=15(1/4)/2\\\\x=\frac{15}{8}\ cups\ of\ pretzel$

Convert to mixed number

$\frac{15}{8}=\frac{8}{8}+\frac{7}{8}=1\frac{7}{8}\ cups\ of\ pretzel$

6 0

3 years ago