If you know the diameter of a circle,
1 answer:
Step-by-step explanation:
a. Area of a circle = πr², where r means radius.
Step 1: converted diameter to radius.
diameter = 2 radius
In other way of writing, radius = diameter.
Step 2: substitute radius into the formula.
Area of a circle = π(d)²
Step 3: substitute π into the formula.
some question is given the value of π), if not substitute 3.14 for π.
Area of a circle = 3.14(d)²
Step 4: substitute d into the formula, then we can solve its area.
b. a. Circumference of a circle = 2πr, where r means radius.
Step 1: converted diameter to radius.
diameter = 2 radius
In other way of writing, radius = diameter.
Step 2: substitute radius into the formula.
C = 2π(d)
Step 3: substitute π into the formula.
some question is given the value of π), if not substitute 3.14 for π.
C = 2(3.14)(d)
Step 4: substitute d into the formula, then we can solve its circumference.
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Answer:
Comparing the p value with the significance level we see that
so we can conclude that we have enough evidence to reject the null hypothesis, and the difference between the two groups is significantly different.
Step-by-step explanation:
represent the mean for sample 1
represent the mean for sample 2
represent the sample standard deviation for 1
represent the sample standard deviation for 2
sample size for the group 2
sample size for the group 2
Significance level provided
t would represent the statistic (variable of interest)
Concepts and formulas to use
We need to conduct a hypothesis in order to check if the difference in the population means, the system of hypothesis would be:
Null hypothesis:
Alternative hypothesis:
We don't have the population standard deviation's, so for this case is better apply a t test to compare means, and the statistic is given by:
(1)
And the degrees of freedom are given by
t-test: Is used to compare group means. Is one of the most common tests and is used to determine whether the means of two groups are equal to each other.
With the info given we can replace in formula (1) like this:
P value
Since is a bilateral test the p value would be:
Comparing the p value with the significance level we see that
so we can conclude that we have enough evidence to reject the null hypothesis, and the difference between the two groups is significantly different.