Words were displayed on a computer screen with background colors of red and blue. results from scores on a test of word recall are given below. use a 0.05 significance level to test the claim that the samples are from populations with the same standard deviation. assume that both samples are independent simple random samples from populations having normmal distributions. does the background color appear to have an effect on the variation of word recall scores? n x sred background 35 15.14 5.91blue background 37 12.42 5.42what are the null and alternative hypotheses?

Yes, the background color appear to have an effect on the variation of word recall scores

Step-by-step explanation:

Given that results from scores on a test of word recall are given are as follows:

Two test scores have independent means and having normal distribution.

(Two tailed test at 5% significance level)

Group   Group One     Group Two  

Mean    15.140012.4200

SD              5.91005.4200

SEM     0.99900.8910

N                35      37      

The mean of Group One minus Group Two equals 2.7200

standard error of difference = 1.335

Hence t statistic = 2.0369

p value = 0.0454

Since p <0.05 we reject null hypothesis

Yes, the background color appear to have an effect on the variation of word recall scores

step-by-step explanation:

abc

d. $180

step-by-step explanation:

if the dimensions of the room is 9ft by 12 ft, we have the area of the floor as,

so the area of the floor is 108 square feet, converting that into square yards we get,

the cost of carpet is $15 per square yard, therefore the cost of carpet for 12 square yards is,

hence, the cost of carpet is $180.

assuming the dimensions of the room be,

15 ft by 12 ft

so, the area of the floor of that room is,

we can convert 180 square feet into square yards, we know that,

1 sq ft = 0.111 sq yard

so, 180 square feet is,

so the area of floor is 20 square yards.

now, the cost of carpet is 15 dollars per square yard, therefore the cost of carpet for 20 square yards is,

so, it will cost $300.