Plz help answer the following questions

A school will offer pizza on Friday's if at least 30% of the students will buy it. A sample of 50 students asked if they would b

Whitepunk [10]

Answer:

0.0614

Step-by-step explanation:

Solution:-

- The school offers pizza on friday when at-least 30% students are willing to buy.

- The minimum required proportion of students, p = 30%

- A sample of n = 50 students were taken and out of the sample x = 10 people responded willing to buy pizza.

- We will denote a random variable X: the number of students willing to buy Pizza on fridays.

- For the sample of n = 50, for Pizza to be offered on friday the expected number of student who should opt for buying must be at-least:

Expected ( Mean - u ) = n*p = 50*0.3 = 15 people.

- The standard deviation for the normal distribution can be determined as follows:

standard deviation ( s ) = √n*p*(1-p)

= √50*0.3*(0.7)

= √10.5 = 3.2404

- We will assume that the random variable X follows normal distribution:

X ~ Norm ( 15 , 3.2404^2 )

- To determine the probability of sample of size n = 50 with proportion or lower. The number of people willing to buy pizza on friday as per survey are x = 10.

- Evaluate the standard normal ( Z-score ):

P ( X < x ) = P ( Z < ( x - u ) / s )

P ( X < 10 ) = P ( Z < ( 10 - 15 ) / 3.2404 )

P ( X < 10 ) = P ( Z < -1.54301 )

- Use the standard normal tables to determine the value of P ( Z < -1.54301 ):

P ( X < 10 ) = P ( Z < -1.54301 ) = 0.0614

Answer: The probability of getting a sample with the proportion or lower given a population with a proportion of .30 is 0.0614.

5 0

3 years ago

Please help me answer this.

inna [77]

Answer:

D. 4,-1

Step-by-step explanation:

The mathmatical way to solev it is to find the linear equation and plug in the points, but i just looked at the graph to see which point was in the shaded region.

5 0

2 years ago

1. The amount of money Travis earns is given in the table.

Anastaziya [24]

Answer:

$250

Step-by-step explanation:

The numbers in the table indicate a proportional relationship between earnings and hours worked. Among other things, that means you can find the earnings for 20 hours by using any table values that sum to 20 hours.

For example, 9 hours + 11 hours = 20 hours, so the earnings would be ...

$112.50 +137.50 = $250.00 . . . for 20 hours

You could also use 4×5 hours = 20 hours, so ...

4×$62.50 = $250 . . . for 20 hours

__

Or, you can figure ...

$37.50/(3 h) = $12.50/h

so the pay for 20 hours is ...

(20 h)×($12.50/h) = $250.00

3 0

2 years ago

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