A portable CD player costs $48. How much is 25% of the cost
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Composing functions means that the input of the outer functions is the output of the inner function.
In fact, you can rewrite the circle notation as
So, we can substitute g(x) with its expression:
And since f(x)=x+5, we simply have to add 5 to its input:
Similarly, we have, substituting f with its expression,
And since g(x)=4x+2, we have to multiply the input by 4 and add 2:
Answer:
1. H0: P1 = P2
2. Ha: P1 ≠ P2
3. pooled proportion p = 0.542
4. P-value = 0.0171
5. The null hypothesis failed to be rejected.
At a signficance level of 0.01, there is not enough evidence to support the claim that there is significant difference between the exercise habits of Science majors and Math majors .
6. The 99% confidence interval for the difference between proportions is (-0.012, 0.335).
Step-by-step explanation:
We should perform a hypothesis test on the difference of proportions.
As we want to test if there is significant difference, the hypothesis are:
Null hypothesis: there is no significant difference between the proportions (p1-p2 = 0).
Alternative hypothesis: there is significant difference between the proportions (p1-p2 ≠ 0).
The sample 1 (science), of size n1=135 has a proportion of p1=0.607.
The sample 2 (math), of size n2=92 has a proportion of p2=0.446.
The difference between proportions is (p1-p2)=0.162.
The pooled proportion, needed to calculate the standard error, is:
The estimated standard error of the difference between means is computed using the formula:
Then, we can calculate the z-statistic as:
This test is a two-tailed test, so the P-value for this test is calculated as (using a z-table):
As the P-value (0.0171) is bigger than the significance level (0.01), the effect is not significant.
The null hypothesis failed to be rejected.
At a signficance level of 0.01, there is not enough evidence to support the claim that there is significant difference between the exercise habits of Science majors and Math majors .
We want to calculate the bounds of a 99% confidence interval of the difference between proportions.
For a 99% CI, the critical value for z is z=2.576.
The margin of error is:
Then, the lower and upper bounds of the confidence interval are:
The 99% confidence interval for the difference between proportions is (-0.012, 0.335).