Answer:
The standard deviation of car age is 2.17 years.
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
68% of the measures are within 1 standard deviation of the mean.
95% of the measures are within 2 standard deviation of the mean.
99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean = 7.5
(a) If 99.7% of the ages are between 1 year and 14 years, what is the standard deviation of car age?
This means that 1 is 3 standard deviations below the mean and 14 is 3 standard deviations above the mean.
So

I want to find 



The standard deviation of car age is 2.17 years.
The answer would be
You got it right
I wish i saw this when i needed jt too
Explanation
Absolutely
A: a horizontal shrink would be caused by cos 3x.
B: a vertical stretch would be caused by 3 cos x
C: a horizontal stretch would be caused by cos (1/3)x
D: a vertical shrink would be caused by 1/3 cos x.
(a) there are 8C2 = 28 ways of picking 2 girls from 8
And there are 21C4 = 5985 ways of picking 4 boys
Required number of ways for 2g / 4b = 28 * 5985 = 167,580
(b) at least 2 girls means combinations of 2g/4b , 3g,3b , 4g/2b , 5g 1b or
6 girls.
2g/4b = 167,580 ways
3g/3b = 8C3 * 21C3 = 56 * 1330 = 74,480
4g/2b = 8C4* 21C2 = 70 * 210 = 14,700
5g 1b = 8C5* 21 = 56*21 = 1176
6 girls = 8C6 = 28
adding these up we get the answer to (b) which is 257,964
Answer:

Step-by-step explanation:
The given parallelogram has vertices R(1, -1), S(6, 1), T(8, 5), and U(3, 3) .
Recall the distance formula;
We use the distance formula to determine the length of the diagonals.
For diagonal R(1,-1) and T(8,5), We have;




For the diagonal S(6,1) U(3,3)




Therefore the shorter diagonal is:
