Ask question

Ask question

All categories

3 years ago

15

Use the appropriate normal distribution to approximate the resulting binomial distributions. A convenience store owner claims th

at 55% of the people buying from her store, on a certain day of the week, buy coffee during their visit. A random sample of 35 customers is made. If the store owner's claim is correct, what is the probability that fewer than 24 customers in the sample buy coffee during their visit on that certain day of the week?

1 answer:

Naddika [18.5K]3 years ago

6 0

Answer:

0.9256

Step-by-step explanation:

Given that a convenience store owner claims that 55% of the people buying from her store, on a certain day of the week, buy coffee during their visit

Let X be the number of customers who buy from her store, on a certain day of the week, buy coffee during their visit

X is Binomial (35, 0.55)

since each customer is independent of the other and there are two outcomes.

By approximation to normal we find that both np and nq are >5.

So X can be approximated to normal with mean = np = 19.25

and std dev = $\sqrt{npq} \\=2.943$

Required probability = prob that fewer than 24 customers in the sample buy coffee during their visit on that certain day of the week

= $P(X$ (after effecting continuity correction)

= 0.9256

You might be interested in

Elsa runs 7 miles in 80 minutes. At the same rate, how many miles would she run in 64 minutes?

charle [14.2K]

Heather runs 7 miles in 80 minutes.

At the same rate, how many miles would she run in 64 minutes?

Let x represent miles would she run in 64 minutes?

Question Sets Up the Proportion

7/80= x/63 |Cross Multiplying to solve for x

x = 7*64/80

x = 5.6mi

Hope this helps!

7 0

3 years ago

Solve the oblique triangle where side a has length 10 cm, side c has length 12 cm, and angle beta has measure thirty degrees. Ro

Ugo [173]

Answer:

$Side\ B = 6.0$

$\alpha = 56.3$

$\theta = 93.7$

Step-by-step explanation:

Given

Let the three sides be represented with A, B, C

Let the angles be represented with $\alpha, \beta, \theta$

[See Attachment for Triangle]

$A = 10cm$

$C = 12cm$

$\beta = 30$

What the question is to calculate the third length (Side B) and the other 2 angles ( $\alpha\ and\ \theta$ )

Solving for Side B;

When two angles of a triangle are known, the third side is calculated as thus;

$B^2 = A^2 + C^2 - 2ABCos\beta$

Substitute: $A = 10$ , $C =12$ ; $\beta = 30$

$B^2 = 10^2 + 12^2 - 2 * 10 * 12 *Cos30$

$B^2 = 100 + 144 - 240*0.86602540378$

$B^2 = 100 + 144 - 207.846096907$

$B^2 = 36.153903093$

Take Square root of both sides

$\sqrt{B^2} = \sqrt{36.153903093}$

$B = \sqrt{36.153903093}$

$B = 6.0128115797$

$B = 6.0$ <em>(Approximated)</em>

Calculating Angle $\alpha$

$A^2 = B^2 + C^2 - 2BCCos\alpha$

Substitute: $A = 10$ , $C =12$ ; $B = 6$

$10^2 = 6^2 + 12^2 - 2 * 6 * 12 *Cos\alpha$

$100 = 36 + 144 - 144 *Cos\alpha$

$100 = 36 + 144 - 144 *Cos\alpha$

$100 = 180 - 144 *Cos\alpha$

Subtract 180 from both sides

$100 - 180 = 180 - 180 - 144 *Cos\alpha$

$-80 = - 144 *Cos\alpha$

Divide both sides by -144

$\frac{-80}{-144} = \frac{- 144 *Cos\alpha}{-144}$

$\frac{-80}{-144} = Cos\alpha$

$0.5555556 = Cos\alpha$

Take arccos of both sides

$Cos^{-1}(0.5555556) = Cos^{-1}(Cos\alpha)$

$Cos^{-1}(0.5555556) = \alpha$

$56.25098078 = \alpha$

$\alpha = 56.3$ <em>(Approximated)</em>

Calculating $\theta$

Sum of angles in a triangle = 180

Hence;

$\alpha + \beta + \theta = 180$

$30 + 56.3 + \theta = 180$

$86.3 + \theta = 180$

Make $\theta$ the subject of formula

$\theta = 180 - 86.3$

$\theta = 93.7$

5 0

3 years ago

Need help with my Geometry, can someone help me with 4,5 and 10?

xz_007 [3.2K]

For questions 4 and 5, use laws of complementary and supplementary angles to find values of x. I'm not too sure about what question 10 is asking.

Hope I helped :)

6 0

3 years ago

Read 2 more answers

What is the y-inercept of the graph of f

Alexxx [7]

<em>y-intercept</em><em> </em><em>is</em><em> </em><em>where</em><em> </em><em>the</em><em> </em><em>line</em><em> </em><em>on</em><em> </em><em>your</em><em> </em><em>graph</em><em> </em><em>crosses</em><em> </em><em>through</em><em> </em><em>the</em><em> </em><em>y-axis</em>

5 0

4 years ago

15% of amount = 112.79

Mazyrski [523]

To find the original amount, you divide the product by the percentage.

112.79 / 0.15 ≈ 751.933 (the 3's repeat infinitely).

To check your answer, multiply 751.933 by 0.15.
751.933 * 0.15 = 112.78995 ≈ 112.79

4 0

3 years ago

Read 2 more answers