The area of a rectangle is 42 square inches
1 answer:
Answer:
The perimeter is 31 inches
Step-by-step explanation:
The perimeter is the sum of all the sides.
The formula for the area of the rectangle is :
To work this out you would first need to divide the area of 42 by the length of 12, this gives you 3.5. This is because the formula for the area of a rectangle is length multiplied by the width, and so by dividing the area by 12 we are working out the perimeter of the missing side.
Now that we know the lengths of both sides we can begin working out the perimeter. You can do this by multiplying the lengths by 2. Multiply 12 by 2,which gives you 24. Multiply 3.5 by 2, which gives you 7.
The final step in calculating the perimeter would be to add the values of 24 and 7, this gives you 31. This is because the perimeter is sum of all of the lengths of a shape.
1) Divide 42 by 12.
2) Multiply 12 by 2.
3) Multiply 3.5 by 2.
4) Add 7 and 24.
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Answer:
b. 35.9, 39.1 ounces
Step-by-step explanation:
Previous concepts
A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".
The margin of error is the range of values below and above the sample statistic in a confidence interval.
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
barX=37.465 represent the sample mean for the sample
population mean (variable of interest)
s=2.27 represent the sample standard deviation
n=10 represent the sample size
Confidence interval
The confidence interval for the mean is given by the following formula:
barX +- t*[(s)/(sqrt{n))] (1)
In order to calculate the critical value t we need to find first the degrees of freedom, given by:
df=n-1=10-1=9
Since the Confidence is 0.95 or 95%, the value of alpha=0.05 and \alpha/2 =0.025, and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-T.INV(0.025,9)".And we see that t_(alpha/2)=2.26
Now we have everything in order to replace into formula (1):
37.465-2.26[(2.27)/(sqrt{10))]=35.9
37.465+2.26[(2.27)/(sqrt{10))]=39.1
So on this case the 95% confidence interval would be given by (35.9;39.1)