<span>Number of values = 5 (There are 5 values given)
Mean = (82 + 44 + 67 + 52 + 120)/5 = 73
Variance = (1/5) [(82-73)^2 + (44-73)^2 + (67-73)^2 + (52-73)^2 + (120-73)^2] = 721.6
Standard deviation = sqrt (721.6) = 26.86</span>
First you figure out that the ratio 7:4 is 1.75
Then you do this problem 28 divided by 1.75=16
And 28:16 is the same as 7:4
Now all you do is add 28+16=44
Answer: 
Step-by-step explanation:
Given
There are 8 red and 4 blue beads
Three beads were taken from the box
(i)No of ways of choosing three red beads out of 12 beads is 
Total no of ways 
Probability is

(ii)atleast two beads refers to minimum two beads
There can be two possibilities (2B,1 R), (3B, 0R)

700/32 = 21.875
He'd have to sell approximately 22 shares to have enough to pay for his vacation.