A cyclist cycles a distance of 40 miles in a time of 4 hours.<br> What is her average speed?<br> mph

Giving brainliest seems like an easy question.

Alik [6]

Answer:

Yes, she is correct

Step-by-step explanation:

All you really have to do is multiply 1/5 and 3/4. We can separate her backyard in 5 equal parts. In one of those parts, we have her garden, and we break it down into 4 pieces, and make three of those tomato gardens. Now if we break all 5 parts of her backyard into 4 pieces, we can double check our answer, and see that there are 20 pieces, but only 3 have tomatoes. Of course, that's only to double check, but you could also use this method as a model.

5 0

3 years ago

What is the formal definition of a <br>square ?

AfilCa [17]

A shape with 4 equal sides.

3 0

3 years ago

Read 2 more answers

The quotient of m and 7

xxTIMURxx [149]

the quotient of m and 7 = m/7

8 0

2 years ago

Aberdine makes a $2,900 purchase on her credit card that has a 21% APR. If she only makes the minimum monthly payment of $70, wh

masya89 [10]

Answer:

45

Step-by-step explanation:

i took the test

4 0

2 years ago

Consider a chemical company that wishes to determine whether a new catalyst, catalyst XA-100, changes the mean hourly yield of i

kolezko [41]

Answer:

Null hypothesis: $\mu = 750$

Alternative hypothesis: $\mu \neq 750$

$t=\frac{811-750}{\frac{19.647}{\sqrt{5}}}=6.943$

$p_v =2*P(t_{4}>6.943)=0.00226$

If we compare the p value and a significance level assumed $\alpha=0.05$ we see that $p_v$ so we can conclude that we reject the null hypothesis, and the actual true mean is significantly different from 750 pounds per hour.

Step-by-step explanation:

Data given and notation

Data: 801, 814, 784, 836,820

We can calculate the sample mean and sample deviation with the following formulas:

$\bar X =\frac{\sum_{i=1}^n X_i}{n}$

$s=\sqrt{\frac{\sum_{i=1}^n (X_i -\bar X)^2}{n-1}}$

$\bar X=811$ represent the sample mean

$s=19.647$ represent the standard deviation for the sample

$n=5$ sample size

$\mu_o =750$ represent the value that we want to test

$\alpha$ represent the significance level for the hypothesis test.

t would represent the statistic (variable of interest)

$p_v$ represent the p value for the test (variable of interest)

State the null and alternative hypotheses to be tested

We need to conduct a hypothesis in order to determine if the mean is different from 750 pounds per hour, the system of hypothesis would be:

Null hypothesis: $\mu = 750$

Alternative hypothesis: $\mu \neq 750$

Compute the test statistic

We don't know the population deviation, so for this case is better apply a t test to compare the actual mean to the reference value, and the statistic is given by:

$t=\frac{\bar X-\mu_o}{\frac{s}{\sqrt{n}}}$ (1)

t-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".

We can replace in formula (1) the info given like this:

$t=\frac{811-750}{\frac{19.647}{\sqrt{5}}}=6.943$

Now we need to find the degrees of freedom for the t distirbution given by:

$df=n-1=5-1=4$

What do you conclude?

Compute the p-value

Since is a two tailed test the p value would be:

$p_v =2*P(t_{4}>6.943)=0.00226$

If we compare the p value and a significance level assumed $\alpha=0.05$ we see that $p_v$ so we can conclude that we reject the null hypothesis, and the actual true mean is significantly different from 750 pounds per hour.

4 0

3 years ago

A cyclist cycles a distance of 40 miles in a time of 4 hours. What is her average speed? mph