Answer:
628
Step-by-step explanation:
We have the standard deviation of the sample, so we use the t-distribution to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 12 - 1 = 11
95% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 11 degrees of freedom(y-axis) and a confidence level of 
. So we have T = 2.2
The margin of error is:
In which s is the standard deviation of the sample and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 665 - 37 = 628 hours.
The answer is 628
Answer:
The correct answer is 75 cubic feet.
Step-by-step explanation:
Volume of each block of cube is 1 cubic foot. Since the block is of the shape of a cube, the side length is 1 foot.
Number of blocks needed to fill the bottom of the the chest is 25.
Height of the chest is 3 feet.
Therefore there are three layers to be filled by blocks. Each layer needs 25 blocks each. Thus number of blocks needed to fill the whole chest is 25 × 3 = 75.
Volume of 75 blocks = Volume of the chest = 75 × 1 = 75 cubic feet.
Therefor the volume of the chest is given by 75 cubic feet.
Answer:
Its a i just took the test
Step-by-step explanation:
negative 5 x less than or equals minus 10
-5x<=-10
divide by -5 (this will flip the inequality)
x>=2
Solution: x>=2
Answer:
7.5
Step-by-step explanation:
3 divided by 2/5
3*5/2=15/2=7.5
