# A world class sprinter ran 200 m in 22.75s. What was her average speed?m/sEnter a number.

8.8

Step-by-step explanation:

speed=distance/time

speed- ?

distance- 200m

time- 22.75s

?=200/22.75

?= 8.791...

round it so that it becomes 8.8

## Related Questions

What is m in this question

-16 because you need to subtract -4 from -12

A hypothesis regarding the weight of newborn infants at a community hospital is that the mean is 6.6 pounds. A sample of seven infants is randomly selected, and their weights at birth are recorded as:
9.0, 7.3, 6.0, 8.8, 6.8, 8.4, and 6.6 pounds.
If Alpha = 0.05,
1. What is the critical t-value?
2. What is the decision for a statistically significant change in average weights at birth at the 5% level of significance?

1. Critical value t=±2.447

2. The null hypothesis is failed to be rejected.

At a significance level of 0.05, there is not enough evidence to support the claim that the birth weight significantly differs from 6.6 lbs.

Step-by-step explanation:

This is a hypothesis test for the population mean.

The claim is that the birth weight significantly differs from 6.6 lbs.

Then, the null and alternative hypothesis are:

The significance level is 0.05.

The sample has a size n=7.

The sample mean is M=7.56.

As the standard deviation of the population is not known, we estimate it with the sample standard deviation, that has a value of s=1.18.

The estimated standard error of the mean is computed using the formula:

Then, we can calculate the t-statistic as:

The degrees of freedom for this sample size are:

For a two-tailed test with 5% level of significance and 6 degrees of freedom, the critical value for t is ±2.447.

As the test statistic t=2.152 is under 2.447 and over -2.447, it falls in the acceptance region, so the effect is not significant. The null hypothesis is failed to be rejected.

At a significance level of 0.05, there is not enough evidence to support the claim that the birth weight significantly differs from 6.6 lbs.

Sample mean and standard deviation calculations:

A. A business is attempting to find the best small town in the United States in which to relocate. As part of the investigation, the elevations of all small towns in the United States are researched. Some towns are located high in the Rockies with elevations over 8,000 feet. There are even some towns located in the south central valley of California with elevations below sea level. These elevations can best be described as which level of datab. The unemployment rate is often used as an indicator of a community’s economic vitality. An unemployment rate is best described as what level of measurement?

a. As given in the question, some towns are located high in the Rockies above the sea level and some are located in the south-central valley of the California below the sea level as well. The meaningful zero does not exists here and the variable of interest is continuous(quantitative). Hence, the elevations can be best described as an interval data.

b. The unemployment rate can not be negative. Therefore, the meaningful zero exist here. Hence, the unemployment rate can be best described as ratio data.

Find the highest common factor (HCF) of 90 and 126

18

Step-by-step explanation:

18*5=90

18*7=126

The greatest common factor(GCF) for 90 and 126 is 18

I need helppp !!! Pls

m < B = 55°

Step-by-step explanation:

The exterior angle of a triangle is the angle formed between one side of a triangle and the extension of its adjacent side. In this given problem, the exterior angle of the Δ ABC is < C. The remote interior angles of < C are < B and < A. The sum of these two remote interior angles is equal to the m < C.

We're also given the information that m< C = 115°, m < A = 4y°, and m < B = (3y + 10)°

Therefore, to solve for the m < B, we can establish the following formula:

m < A + m < B = m < C

4y° + (3y + 10)° = 115°

4y° + 3y° + 10° = 115°

7y° + 10° = 115°

Subtract 10° from both sides:

7y° + 10° - 10°  = 115° - 10°

7y° = 105°

Divide both sides by 7 to solve for y:

7y°/7 = 105°/7

y = 15°

Therefore, the value of y = 15. To verify whether this is the correct value, substitute y = 15 into the equality statement:

m < A + m < B = m < C

4(15)° + [3(15) + 10]° = 115°

60° + 55° = 115°

115° = 115° (True statement, which means that y = 15 is the correct value).

Therefore, m < B = (3y + 10)° = 55°

upike 5 1/2 miles from your house to a skatepark you travel one half of that distance in the woods Buck along the bank of a stream for the last half of the woods on how many miles of your trip do you bike along the bank of the stream ​