Please help me I'm being timed

After Halloween, a variety store had some costumes regularly priced at $20.50 on sale for 20% off the regular price. A few weeks

Diano4ka-milaya [45]

20.50 * 0.8 = $16.40

16.40 * 0.4 = $6.56

Final selling price = $6.56

6 0

3 years ago

The Nike store is having a SALE!!! A toddler suit with an original cost of $54 is marked down to $22.95. How much is the discoun

pishuonlain [190]

Answer:

The Discount Percent is 57.50% and the Discount Amount is $31.05

Step-by-step explanation:

To find the discount percent you use the formula D = (L - S) / L x 100. To find the discount amount you take the inital list price and subtract it from the sale price.

4 0

3 years ago

The probability that your call to a service line is answered in less than 30 seconds is 0.85. Assume that your calls are indepen

aev [14]

Answer:

a) 0.1720

b) 0.8298

c) 19

Step-by-step explanation:

For each call, there are only two possible outcomes. Either they are answered in less than 30 seconds. Or they are not. The probabilities for each call are independent. So we use the binomial probability distribution to solve this question.

Binomial probability distribution

The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

In which $C_{n,x}$ is the number of different combinations of x objects from a set of n elements, given by the following formula.

$C_{n,x} = \frac{n!}{x!(n-x)!}$

And p is the probability of X happening.

In this problem we have that:

$p = 0.85$

(a) If you call 12 times, what is the probability that exactly 9 of your calls are answered within 30 seconds? Round your answer to four decimal places (e.g. 98.7654).

This is $P(X = 9)$ when $n = 12$ .

So

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

$P(X = 9) = C_{12,9}.(0.85)^{9}.(0.15)^{3} = 0.1720$

(b) If you call 20 times, what is the probability that at least 16 calls are answered in less than 30 seconds? Round your answer to four decimal places (e.g. 98.7654).

This is $P(X \geq 16)$ when $n = 20$

So

$P(X \geq 16) = P(X = 16) + P(X = 17) + P(X = 18) + P(X = 19) + P(X = 20)$

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

$P(X = 16) = C_{20,16}.(0.85)^{16}.(0.15)^{4} = 0.1821$

$P(X = 17) = C_{20,17}.(0.85)^{17}.(0.15)^{3} = 0.2428$

$P(X = 18) = C_{20,18}.(0.85)^{18}.(0.15)^{2} = 0.2293$

$P(X = 19) = C_{20,19}.(0.85)^{19}.(0.15)^{1} = 0.1368$

$P(X = 20) = C_{20,20}.(0.85)^{20}.(0.15)^{0} = 0.0388$

So

$P(X \geq 16) = P(X = 16) + P(X = 17) + P(X = 18) + P(X = 19) + P(X = 20) = 0.1821 + 0.2428 + 0.2293 + 0.1368 + 0.0388 = 0.8298$

(c) If you call 22 times, what is the mean number of calls that are answered in less than 30 seconds? Round your answer to the nearest integer.

The expected value of the binomial distribution is:

$E(X) = np$

In this question, we have $n = 22$

So

$E(X) = 22*0.85 = 18.7$

The nearest integer to 18.7 is 19.

7 0

3 years ago

Please solve with working out simultaneous equations 3x+2y=12 2x+2y=10

Novay_Z [31]

Here, 3x + 2y = 12
2x + 2y = 10

Subtract 2nd from 1st equation,
x = 2

Now, substitute in 2nd,
2(2) + 2y = 10
2y = 10 - 4
y = 6/2
y = 3

In short, Your Answer would be: (2, 3)

Hope this helps!

4 0

3 years ago

Read 2 more answers

What is the future value of a R 75 000 deposit made every 6 months for 3 years using an annual rate of 10% compounded semi-annua

dolphi86 [110]

Answer:

The future value is: RS 132867.075

Step-by-step explanation:

Given

$PV = 75000$ --- present value