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3 years ago

6

You pack sandwiches for a mountain hike with your friends. Each sandwich takes 2 slices of bread, and you pack 3 sandwiches for

each hiker. How many slices of bread are used for n hikers? Write your answer as an expression.

1 answer:

umka2103 [35]3 years ago

6 0

2x+3m=p because you don't know how many people there are you put a variable in place for that

You might be interested in

Simplify the expression below. (–7x + 4) – (2x – 8)

Elanso [62]

Answer:

- 9x + 12

Step-by-step explanation:

Given

(- 7x + 4) - (2x - 8) ← distribute parenthesis by 1 and - 1

= - 7x + 4 - 2x + 8 ← collect like terms

= - 9x + 12

5 0

3 years ago

(43 points) In the US, 85% of the population has Rh positive blood. Suppose we take a random sample of 6 persons and let Y denot

VladimirAG [237]

Answer:

a) Binomial distribution with parameters p=0.85 q=0.15 n=6

b) 62.29%

c) 2.38%

d) See explanation below

Step-by-step explanation:

a)

We could model this situation with a binomial distribution

$P(6;k)=\binom{6}{k}p^kq^{6-k}$

where P(6;k) is the probability of finding exactly k people out of 6 with Rh positive, p is the probability of finding one person with Rh positive and q=(1-p) the probability of finding a person with no Rh.

So

$\bf P(Y=k)=\binom{6}{k}(0.85)^k(0.15)^{6-k}$

b)

The probability that Y is less than 6 is

P(Y=0)+P(Y=1)+...+P(Y=5)

Let's compute each of these terms

$P(Y=0)=P(6;0)=\binom{6}{0}(0.85)^0(0.15)^{6}=1.139*10^{-5}$

$P(Y=1)=P(6;1)=\binom{6}{1}(0.85)^1(0.15)^{5}=0.0000387281$

$P(Y=2)=P(6;2)=\binom{6}{2}(0.85)^2(0.15)^{4}=0.005486484$

$P(Y=3)=P(6;3)=\binom{6}{3}(0.85)^3(0.15)^{3}=0.041453438$

$P(Y=4)=P(6;4)=\binom{6}{4}(0.85)^4(0.15)^{2}=0.176177109$

$P(Y=5)=P(6;5)=\binom{6}{5}(0.85)^5(0.15)^{1}=0.399334781$

and adding up these values we have that the probability that Y is less than 6 is

$\sum_{i=1}^{5}P(Y=i)=0.622850484\approx 0.6229=62.29\%$

c)

In this case is a binomial distribution with n=200 instead of 6.

p and q remain the same.

The mean of this sample would be 85% of 200 = 170.

In a binomial distribution, the standard deviation is

$s = \sqrt{npq}$

In this case

$\sqrt{200(0.85)(0.15)}=5.05$

<em>Let's approximate the distribution with a normal distribution with mean 170 and standard deviation 5.05</em>

So, the approximate probability that there are fewer than 160 persons with Rh positive blood in a sample of 200 would be the area under the normal curve to the left of 160

(see picture attached)

We can compute that area with a computer and find it is

0.0238 or 2.38%

d)<em> In order to approximate a binomial distribution with a normal distribution we need a large sample like the one taken in c).</em>

In general, we can do this if the sample of size n the following inequalities hold:

$np\geq 5 \;and\;nq \geq 5$

in our case np = 200*0.85 = 170 and nq = 200*0.15 = 30

4 0

2 years ago

A scientist measured the amount of rain that fell in a town during

allochka39001 [22]

Answer:

1.47 mm

Step-by-step explanation:

In week 1 there was 2.6 mm

In week 4 there was 4.07

You want to find the difference of week 1 and 4 meaning you have to subtract week 4's value from week 1's to find how much more rain there was in week 4 than week 1

You would do 4.07-2.6

This is equal to 1.47

THEREFORE there was 1.47 mm more rain in week 4 than week 1

6 0

3 years ago

According to the cost principle, land that was originally acquired for $85,000 is offered for sale at $150,000, is assessed for

Anit [1.1K]

Pretty sure thats the answer $137,000

6 0

3 years ago

Read 2 more answers

Which table belongs to the equation y = 4x - 4?*

fenix001 [56]

Answer:

Could you maybe provide the answer choices?

Step-by-step explanation:

7 0

2 years ago