Ask question

Ask question

All categories

3 years ago

6

10 out of every 65 students order pizza for lunch. There are 416 students at her school. How many students will eat pizza at her

school?

1 answer:

Studentka2010 [4]3 years ago

3 0

Answer:

64

Step-by-step explanation:

First, you divide 416 by 65. This gets you 6.4. But it's not 1 in 65 eating pizza, it's 10 out of 65, so then you multiply 6.4 by 10, getting 64.

You might be interested in

A shipment of 50 precision parts including 4 that are defective is sent to an assembly plant. The quality control division selec

natali 33 [55]

Answer:

0.3968 = 39.68% probability this shipment passes inspection.

Step-by-step explanation:

The parts are chosen without replacement, which means that the hypergeometric distribution is used to solve this question.

Hypergeometric distribution:

The probability of x successes is given by the following formula:

$P(X = x) = h(x,N,n,k) = \frac{C_{k,x}*C_{N-k,n-x}}{C_{N,n}}$

In which:

x is the number of successes.

N is the size of the population.

n is the size of the sample.

k is the total number of desired outcomes.

Combinations formula:

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

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

In this question:

50 parts means that $N = 50$

4 defective means that $k = 4$

10 are chosen, which means that $n = 10$

What is the probability this shipment passes inspection?

Probability that none is defective, so:

$P(X = x) = h(x,N,n,k) = \frac{C_{k,x}*C_{N-k,n-x}}{C_{N,n}}$

$P(X = 0) = h(0,50,10,4) = \frac{C_{4,0}*C_{46,10}}{C_{50,10}} = 0.3968$

0.3968 = 39.68% probability this shipment passes inspection.

6 0

2 years ago

A = 12 and b = 24 ,what Is the area of the pencil

dezoksy [38]

Their is not a lot of information but I think it is 12*24=288

6 0

2 years ago

Professor Turner wrote the expression below on the chalkboard for his team at the Research Center. He asked the scientists there

Lynna [10]

Answer:

12x + 18y + 6z + 4x - 4z

Step-by-step explanation:

Given the expression : 3(4x + 6y + 2z) + 4(x – z)

To eliminate the parenthesis ; we use the distributive property :

3(4x + 6y + 2z) + 4(x – z) becomes ;

3*4x + 3*6y + 3*2z + 4*x + 4*-z

12x + 18y + 6z + 4x - 4z

Hence,

12x + 4x + 18y + 6z - 4z

16x + 18y + 2z

6 0

2 years ago

A manager at a local company asked his employees how many times they had given blood in the last year. The results of the survey

Lubov Fominskaja [6]

Answer:

$Var(X) = E(X^2) -[E(X)]^2 = 4.97 -(1.61)^2 =2.3779$

And the deviation would be:

$Sd(X) =\sqrt{2.3779}= 1.542 \approx 1.54$

Step-by-step explanation:

For this case we have the following distribution given:

X 0 1 2 3 4 5 6

P(X) 0.3 0.25 0.2 0.12 0.07 0.04 0.02

For this case we need to find first the expected value given by:

$E(X) = \sum_{i=1}^n X_i P(X_I)$

And replacing we got:

$E(X)= 0*0.3 +1*0.25 +2*0.2 +3*0.12 +4*0.07+ 5*0.04 +6*0.02=1.61$

Now we can find the second moment given by:

$E(X^2) =\sum_{i=1}^n X^2_i P(X_i)$

And replacing we got:

$E(X^2)= 0^2*0.3 +1^2*0.25 +2^2*0.2 +3^2*0.12 +4^2*0.07+ 5^2*0.04 +6^2*0.02=4.97$

And the variance would be given by:

$Var(X) = E(X^2) -[E(X)]^2 = 4.97 -(1.61)^2 =2.3779$

And the deviation would be:

$Sd(X) =\sqrt{2.3779}= 1.542 \approx 1.54$

8 0

3 years ago

Solve Y, using the Pythagorean Theorem.

olchik [2.2K]

Answer:

y = 8.9

Step-by-step explanation:

8^2 + y^2 = 12^2

64 + y^2 = 144

subtract 64 from both sides

y^2 = 80

square root both sides

y = square root 80

y = 8.9

7 0

2 years ago

Read 2 more answers