Answer: X=9
Step-by-step explanation:
Answer:
D)Yes, because the difference in the means in the actual experiment was more than two standard deviations from 0.
Step-by-step explanation:
We will test the hypothesis on the difference between means.
We have a sample 1 with mean M1=18.2 (drug group) and a sample 2 with mean M2=15.9 (no-drug group).
Then, the difference between means is:

If the standard deviation of the differences of the sample means of the two groups was 1.1 days, the t-statistic can be calculated as:

The critical value for a two tailed test with confidence of 95% (level of significance of 0.05) is t=z=1.96, assuming a large sample.
This is approximately 2 standards deviation (z=2).
The test statistict=2.09 is bigger than the critical value and lies in the rejection region, so the effect is significant. The null hypothesis would be rejected: the difference between means is significant.
Answer:
2z + 3
Step-by-step explanation:
5z + -3z is 2
2z + 3
Answer:
(9b + 3c + 10d)cm
Step-by-step explanation:
Given the sides of a triangle expressed as (2b+c), (7b + 4d) and (6d+2c). The perimeter of the triangle is the sum of all the sides of the triangles.
Perimeter of the triangle = 2b+c + 7b+4d + 6d+2c
Perimeter of the triangle = 2b + 7b + c + 2c + 4d + 6d
Perimeter of the triangle = 9b + 3c + 10d
Hence the perimeter of the triangle is (9b + 3c + 10d)cm
Answer:
area of the floor = 540*840.
=453600 cm sq.
area of the marbal piece = 1/2 * 40* 30 = 600 cm sq.
now,
no. of marble piece reqd. = 453600 / 600 = 756 marbal piece.
hope it helps u.