A toy store marks down every toy by 15% in June. How much does a toy cost during June?

Suppose the coordinate of a is 0, ar = 5, and at =7. What are the possible coordinates of the midpoint of rt ?

77julia77 [94]

Here 'a' corresponds to 0.

Now there are two possibilities for 'r' & 't'

Case 1.

They are on the same side to the right of 'a'

In that case 'r' corresponds to 5 & 't' corresponds to 7.

The midpoint of 'r' and 't' shall be $\frac{5+7}{2} =6$

Case 2.

Both are on the left of 'a'.

In that case 'r' corresponds to -5 & 't' corresponds to -7

The midpoint shall be $\frac{-7-5}{2} =-6$

Case 3.

'r' in on the right of 'a' and 't' is on the left of 'a'

So 'r' corresponds to 5 and 't' corresponds to -7

The midpoint shall be $\frac{-7+5}{2}=-1$

Case 4.

'r' is on the left of 'a' & 't' is on the right of 'a'.

'r' corresponds to -5 & 't' corresponds to 7

The midpoint shall be $\frac{-5+7}{2}=1$

The possible coordinates of the midpoints of rt are 6, -6, 1, -1.

4 0

4 years ago

A survey of 2306 adult Americans aged 18 and older conducted by Harris Interactive found that 417 have donated blood in the past

disa [49]

Answer:

a) p = 0.1808

b) Since 341.54 ≥ 10. Therefore the requirements for constructing a confidence interval for p is satisfied.

c) The interval is (0.1676, 0.194)

d) We are 90% confident that the population proportion of adult Americans who have donated blood in the past two years is between 0.1676 and 0.194

Step-by-step explanation:

Given that:

n = 2306 and x =417

a) Obtain a point estimate for the population proportion (p) is the ratio of sample successes to sample size.

Therefore: p = x / n = 417 / 2306 = 0.1808

p = 0.1808

b) requirements for constructing a confidence interval for p is given by:

np(1-p) ≥ 10

Therefore: np(1-p) = 2306(0.1808)(1 - 0.1808) = 341.54 ≥ 10

Since 341.54 ≥ 10. Therefore the requirements for constructing a confidence interval for p is satisfied.

c) c = 90% = 0.9

α = 1 - 0.9 = 0.1

α / 2 = 0.1 /2 = 0.05

From the probability table, $z_{\frac{\alpha}{2} } = 1.645$

Margin of error (e) = $z_{\frac{\alpha}{2} } \sqrt{\frac{p(1-p)}{n} } =1.645* \sqrt{\frac{0.1808(1-0.1808)}{2306} }=0.0132$

The boundaries are (p - e, p + e) = (0.1808 - 0.0132, 0.1808 + 0.0132) = (0.1676, 0.194)

The interval is (0.1676, 0.194)

d) We are 90% confident that the population proportion of adult Americans who have donated blood in the past two years is between 0.1676 and 0.194

6 0

3 years ago

Read 2 more answers

Cards are drawn, one at a time, from a standard deck; each card is replaced before the next one is drawn. Let X be the number of

steposvetlana [31]

Cards are drawn, one at a time, from a standard deck; each card is replaced before the next one is drawn. Let X be the number of draws necessary to get an ace. Find E(X) is given in the following way

Step-by-step explanation:

From a standard deck of cards, one card is drawn. What is the probability that the card is black and a jack? P(Black and Jack) P(Black) = 26/52 or ½ , P(Jack) is 4/52 or 1/13 so P(Black and Jack) = ½ * 1/13 = 1/26

A standard deck of cards is shuffled and one card is drawn. Find the probability that the card is a queen or an ace.

P(Q or A) = P(Q) = 4/52 or 1/13 + P(A) = 4/52 or 1/13 = 1/13 + 1/13 = 2/13

WITHOUT REPLACEMENT: If you draw two cards from the deck without replacement, what is the probability that they will both be aces?

P(AA) = (4/52)(3/51) = 1/221.

WITHOUT REPLACEMENT: What is the probability that the second card will be an ace if the first card is a king?

P(A|K) = 4/51 since there are four aces in the deck but only 51 cards left after the king has been removed.

WITH REPLACEMENT: Find the probability of drawing three queens in a row, with replacement. We pick a card, write down what it is, then put it back in the deck and draw again. To find the P(QQQ), we find the

probability of drawing the first queen which is 4/52.

The probability of drawing the second queen is also 4/52 and the third is 4/52.

We multiply these three individual probabilities together to get P(QQQ) =

P(Q)P(Q)P(Q) = (4/52)(4/52)(4/52) = .00004 which is very small but not impossible.

Probability of getting a royal flush = P(10 and Jack and Queen and King and Ace of the same suit)

5 0

3 years ago

The product of 17 and a number

Over [174]

<span>17 x X = A, i think.</span>

8 0

3 years ago

A ladder is 80 inches tall. How tall is it in feet and inches?

Veseljchak [2.6K]

Answer:

6'8

Step-by-step explanation:

6 0

3 years ago

Read 2 more answers