I only need help with a through d. Please help me, I would really appreciate it.

A large chocolate bar has a base area of 47.1 square feet and it’s length is 0.7 feet longer than twice it’s width. Find the len

VLD [36.1K]

Answer:

The dimensions of the bar are width = 4.68099 feet and length = 10.06198 feet

Step-by-step explanation:

A chocolate bar has a rectangular shape, therefore it's area is given by the following formula:

area = width*length

In this case the length is 0.7 feet longer than twice the width, therefore:

length = 2*width + 0.7

Applying the second equation on the first one and using the data from the question we have:

47.1 = width*(2*width + 0.7)

47.1 = 2*width² + 0.7*width

2*width² + 0.7*width = 47.1

width² + 0.35*width = 23.55

width = $\frac{-0.35 \pm \sqrt{0.35^2 -4*1*(-23.55)}}{2*1} = -0.175 \pm 4,85599$

width = 4.68099 or width = -5.03099

Since the width can't be negative, it can only be 4.68099 feet.

length = 2*4.68099 + 0.7 = 10.06198 feet.

6 0

3 years ago

Admission to a car show costs $5 for each ticket. After selling only 20 tickets, they decided to lower the price to $3 each. If

Naddik [55]

First you would multiple 5 × 20 which equals $100 then you would subtract $217 by $100 and you would get 39 tickets and then you would add your twenties tickets and your 39 tickets together to get your answer which is 59 tickets.

5 0

3 years ago

Read 2 more answers

The length of each side of a regular pentagon is increased by 8 inches, so the perimeter is now 65 inches. What is the original

evablogger [386]

Here as the Pentagon is regular so it's all sides will be of equal length . And if we assume It's each side be s , then it's perimeter is going to be (s+s+s+s+s) = 5s.And as here , each side is increased by 8 inches and then it's perimeter is 65 inches , so we got that it's side after increament is (s+8) inches and original length is s inches . And if it's each side is (s+8) inches , so it's perimeter will be 5(s+8) and as it's equal to 65 inches . So , 5(s+8) = 65

${:\implies \quad \sf 5(s+8)=65}$

${:\implies \quad \sf 5s+5\times 8=65}$

${:\implies \quad \sf 5s+40=65}$

${:\implies \quad \sf 5s=65-40}$

${:\implies \quad \sf 5s=25}$

${:\implies \quad \sf s=\dfrac{25}{5}=5}$

${:\implies \quad \bf \therefore \quad \underline{\underline{s=5\:\: Inches}}}$

As we assumed the original side to be s .

Hence, the original side's length 5 inches 

8 0

2 years ago

An investigator thinks that people under the age of forty have vocabularies that are different than those of people over sixty y

Kay [80]

Answer:

$t=\frac{(14-20)-0}{\sqrt{\frac{5^2}{31}+\frac{6^2}{31}}}}=-4.28$

Now we can calculate the p value with the following probability:

$p_v =2*P(t_{60}$

The p value is a very low value so then we have enough evidence to reject the null hypothesis and we can conclude that people under the age of forty have vocabularies that are different than those of people over sixty years of age.

Step-by-step explanation:

Information given

$\bar X_{1}=14$ represent the mean for sample 1 (younger)

$\bar X_{2}=20$ represent the mean for sample 2 (older)

$s_{1}=5$ represent the sample standard deviation for 1

$s_{f}=6$ represent the sample standard deviation for 2

$n_{1}=31$ sample size for the group 2

$n_{2}=31$ sample size for the group 2

t would represent the statistic

System of hypothesis

We want to test if that people under the age of forty have vocabularies that are different than those of people over sixty years of age, the system of hypothesis are:

Null hypothesis: $\mu_{1}-\mu_{2}=0$

Alternative hypothesis: $\mu_{1} - \mu_{2}\neq 0$

The statistic is given by:

$t=\frac{(\bar X_{1}-\bar X_{2})-\Delta}{\sqrt{\frac{\sigma^2_{1}}{n_{1}}+\frac{\sigma^2_{2}}{n_{2}}}}$ (1)

And the degrees of freedom are given by $df=n_1 +n_2 -2=31+31-2=60$

Replacing the info given we got:

$t=\frac{(14-20)-0}{\sqrt{\frac{5^2}{31}+\frac{6^2}{31}}}}=-4.28$

Now we can calculate the p value with the following probability:

$p_v =2*P(t_{60}$

The p value is a very low value so then we have enough evidence to reject the null hypothesis and we can conclude that people under the age of forty have vocabularies that are different than those of people over sixty years of age.

6 0

3 years ago

What is the variance of the following data? If necessary, round your answer to two decimal places. 17, 13, 13, 22, 11, 20

Bond [772]

Variance is the standard deviation squared but we're not going to use that now. Let's first calculate the mean:

mean = (17+13+13+22+11+20)/6 = 16.

Now for each value, let's see how far it is from this mean. We'll square these distances and average them. That's our variance.

17 distance 1 squared = 1
13 distance 3 squared = 9
13 distance 3 squared = 9
22 distance 6 squared = 36
11 distance 5 squared = 25
20 distance 4 squared = 16

Now average these outcomes:

variance = (1+9+9+36+25+16)/6 = 16.

So the variance by coincidence is the same as the mean.

Answer C is your answer.

7 0

3 years ago