Answer:
0.918 is the probability that the sample average sediment density is at most 3.00
Step-by-step explanation:
We are given the following information in the question:
Mean, μ = 2.80
Standard Deviation, σ = 0.85
Sample size,n = 35
We are given that the distribution of sediment density is a bell shaped distribution that is a normal distribution.
Formula:
Standard error due to sampling:

P(sample average sediment density is at most 3.00)
Calculation the value from standard normal z table, we have,
0.918 is the probability that the sample average sediment density is at most 3.00
Answer:
c
Step-by-step explanation:
I find it convenient to look at the differences and the rate at which those differences are made up.
8. Jim is closing the $150 gap at the rate of $7.50 per week. He will catch up in
... 150/(7.5/week) = 20 weeks
9. At noon, the price of Stock A has increased by 0.05×3 = 0.15, so is now $15.90, which is $0.63 more than Stock B at that time. The prices are closing the gap at the rate of $0.05 +0.13 = $0.18 per hour, so will be the same after
... $0.63/($0.18/hour) = 3.5 hours . . . . after noon, at 3:30 pm
_____
You can also write and solve equations for the prices of the stocks. Or you can use a graphing calculator to tell you the solution. When equations are involved, I like to solve them the simplest possible way: let technology do it.
You are given the value at a time, and the rate of change of that value, so the equations are easily written in point-slope form. You will note that the common price at 3:30 pm (15.5 hours after midnight) is one that is not a whole number of cents. (That's usually OK for when trading stocks.)
That's addition of mixed numbers. Convert 3/7 and 5/9 to fractions with the denominator (7)(9) = 63 (this is the LCD):
10 27/63 + 19 35/63
This comes out to 29 62/63.