What is the answer for this math 4- -13=!
1 answer:
You might be interested in
Answer:
We conclude that the students that took the Kaplan tutoring have a mean score greater than 29.5.
Step-by-step explanation:
We are given that the Kaplan tutoring company obtains a sample of 40 students with a mean MCAT score of 32.2 with a standard deviation of 4.2.
Let = <u><em>population mean score</em></u>
So, Null Hypothesis, :
29.5 {means that the students that took the Kaplan tutoring have a mean score less than or equal to 29.5}
Alternate Hypothesis, :
> 29.5 {means that the students that took the Kaplan tutoring have a mean score greater than 29.5}
The test statistics that will be used here is <u>One-sample t-test statistics</u> because we don't know about population standard deviation;
T.S. = ~
where, = sample mean MCAT score = 32.2
s = sample standard deviation = 4.2
n = sample of students = 40
So, <u><em>the test statistics</em></u> = ~
= 4.066
The value of t-test statistics is 4.066.
Now, at 0.05 level of significance, the t table gives a critical value of 1.685 at 39 degrees of freedom for the right-tailed test.
Since the value of our test statistics is more than the critical value of t as 4.066 > 1.685, so <u><em>we have sufficient evidence to reject our null hypothesis</em></u> as it will fall in the rejection region.
Therefore, we conclude that the students that took the Kaplan tutoring have a mean score greater than 29.5.
Answer:
The time taken by smaller pipe to fill the tank alone is 74.2 min
Step-by-step explanation:
Given as :
The time taken by two pipes to fill tank = 19 min
Let the time taken by larger pipe to fill tank = y
And the time taken by smaller pipe to fill tank = x
According to question
The smaller pipe takes 49 minutes longer than larger pipe
I.e x = y + 49
Now,
+
=
Or, +
=
Or, =
Or, 2 y + 49 =
Or, 19 × ( 2 y + 49 ) = y² + 49 y
Or, 38 y + 931 = y² + 49 y
Or, y² + 49 y - 38 y - 931 = 0
or, y² + 11 y - 931 = 0
Or, Applying quadratic equation method to calculate the value of y
so, y =
Or, y =
Or, y =
or, y =
or, y =
∴ y = 25.2 , - 36.5
So, The time taken by larger pipe = y = 25.2 min
and the time taken by smaller pipe to fill the tank = y + 49 = 25.2 + 49 = 74.2 min
Hence The time taken by smaller pipe to fill the tank alone is 74.2 min answer