Please help i can’t figure this out

Sally gets a cup of coffee and a muffin every day for breakfast from one of the many coffee shops in her neighborhood. She picks

aniked [119]

Answer:

A. Mean of the amount Sally spends on breakfast daily = $ 3.90

Standard deviation of the amount Sally spends on breakfast daily = $ 0.34 (rounding to the next cent)

B. Mean of the amount Sally spends on breakfast weekly = $ 27.30

Standard deviation of the amount Sally spends on breakfast weekly = $ 0.89 (rounding to the next cent)

Step-by-step explanation:

1. Let's review the information given to us to answer the question correctly:

Average price of a cup of coffee = $ 1.40

Standard deviation = $0.30

Average price of a muffin = $ 2.50

Standard deviation = $ 0.15

The two prices are independent of each other

2. What is the mean and standard deviation of the amount Sally spends on breakfast daily?

Let's recall that:

1. The mean of the sum of two independent variables is the sum of their means.

2. The variance of the sum of two independent variables is equal to the sum of their variances.

Therefore,

Mean of the amount Sally spends on breakfast daily = Average price of a cup of coffee + Average price of a muffin

Replacing with the values we know:

Mean of the amount Sally spends on breakfast daily = 1.40 + 2.50

Mean of the amount Sally spends on breakfast daily = $ 3.90

Variance of the amount Sally spends on breakfast daily = Variance of the price of a cup of coffee + Variance of the price of a muffin

Replacing with the values we know:

Variance of the amount Sally spends on breakfast daily = 0.30² + 0.15²

Variance of the amount Sally spends on breakfast daily = 0.1125

Standard deviation of the amount Sally spends on breakfast daily = √0.1125

Standard deviation of the amount Sally spends on breakfast daily = $ 0.34 (rounding to the next cent)

3. What is the mean and standard deviation of the amount she spends on breakfast weekly (7 days)?

Mean of the amount Sally spends on breakfast weekly = 7 * Mean of the amount Sally spends on breakfast daily

Mean of the amount Sally spends on breakfast weekly = 7 * 3.90

Mean of the amount Sally spends on breakfast weekly = $ 27.30

Variance of the amount Sally spends on breakfast weekly = 7 * Variance of the amount Sally spends on breakfast daily

Variance of the amount Sally spends on breakfast weekly = 7 * 0.1125

Variance of the amount Sally spends on breakfast weekly = 0.7875

Standard deviation of the amount Sally spends on breakfast weekly = √0.7875

Standard deviation of the amount Sally spends on breakfast weekly = $ 0.89 (rounding to the next cent)

3 0

3 years ago

Mr. Johnson sells erasers for $3 each. He sold 96 last week and he sold 204 this week. About how much more money did he make thi

emmasim [6.3K]

Answer:

He makes $324 more this week than last week.

Step-by-step explanation:

8 0

2 years ago

Read 2 more answers

10 points! Please help if able!

TEA [102]

The 30/60/90 right triangle is the biggest cliche in trig. We recall the sides come in ratio $1:\sqrt{3}:2$

$1:\sqrt{3}:2 = x:y:4\sqrt{2}$

First x:

$\dfrac x 1 = \dfrac{4 \sqrt{2}}{2}$

$x = 2 \sqrt 2$

Next y:

$\dfrac{y}{\sqrt{3}} =\dfrac{x}{1}$

$y= 2 \sqrt{2} \sqrt{3} = 2 \sqrt{6}$

Choice C

3 0

3 years ago

Priya filled 5 jars, using a total of 7 ½ cups of strawberry jam. How many cups of jam are in each jar?

Leya [2.2K]

Answer:

1 1/2 cups of jam per jar

Step-by-step explanation:

Divide 7 1/2 by 5 to get 1 1/2 cups of jam per jar.

6 0

3 years ago

State if the two triangles are congruent, if they are state how you know.

Mnenie [13.5K]

Answer:

I belive it would be HL because its defenitly not SSS

Step-by-step explanation:

HL Postulate is if the hypotenuse and leg of one right triangle are congruent to the hypotenuse and leg of another right triangle, then the two triangles are congruent.

4 0

3 years ago