Answer:

And we can assume a normal distribution and then we can solve the problem with the z score formula given by:

And replacing we got:


We can find the probability of interest using the normal standard table and with the following difference:

Step-by-step explanation:
Let X the random variable who represent the expense and we assume the following parameters:

And for this case we want to find the percent of his expense between 38.6 and 57.8 so we want this probability:

And we can assume a normal distribution and then we can solve the problem with the z score formula given by:

And replacing we got:


We can find the probability of interest using the normal standard table and with the following difference:

The answer to this is 1 pound and 4 ounces.
Answer:
RS = 2
Step-by-step explanation:
Points R, S, and T are collinear, and S is between R and T, in addition, RS = 2x-4, ST = 3x+2, and RT = 13. Find the value of RS
Hence:
RS + ST = RT
2x - 4 + 3x + 2 = 13
2x + 3x - 4 + 2 = 13
5x - 2 = 13
5x = 13 + 2
5x = 15
x = 15/5
x = 3
To find the value of RS
RS = 2x-4
RS = 2 × 3 - 4
RS = 6 - 4
RS = 2