She has a difference of $2.75, she may have subtracted something wrong while balancing out the check book.
Standard deviations of the four activities of the critical path are 1,2,4,2.
Standard deviation of this critical path = Sum of square root of variance of this corresponding critical path
Standard deviation of critical path 



Now we need to find the probability that the project will completed in 38 weeks given that its expected completion time is 40 weeks.
That is, we need to find P(X<38) :


Probability 
Thus the probability that the project will be completed in 38 weeks is 0.34.
Answer:
Option B. 1990 - 1992
Step-by-step explanation:
If we have to calculate inflation rate in year 2000 from 1990, we use the formula

which means if consumer price index is increasing year by year the inflation rate will increase.
Now we analyse our options given with the help of graph given.
A. from 1994 - 2000
Consumer price index increased from year 1994 to 1998 but decreased between 1998 to 2000.
So this option doesn't show the continuous inflation.
B. Year 1990 - 1992
We find a continuous increase in C.P.I. therefore there will be a continuous increase in inflation.
So this option is correct.
C. Year 1992 - 1996
In this gap we see deflation from year 1992 to 1994 then inflation between 1994 - 1996.
So there is ups and downs in this period showing discontinuity in inflation.
D. 1992 - 1994
There is continuous decrease in C.P.I. so continuous deflation is reported between this period.
It's not the correct option.
Answer is Option B.
In this question , we have to simplify the given ratio, which is
12xy:3x
First we have to see which factor is common in numerator and denominator,
We can write 12 as 3 times 4, that is

So the common factor is 3x.
In the next step, we cancel out 3x

And that's the required simplified form .
Answer:

Step-by-step explanation:
Given



Required
Probability of selecting 2 orange marbles
The total number of marbles is:



The probability that the first selection is orange is:

Because it is a selection without replacement, the number of orange marbles and the total number of marbles would decrease by 1, respectively.
So, the probability that the selection is orange is:


The required probability is:




