Given:
A line contains the points R(-1, 8), S(1, 4) and T(6, y).
To find:
The value of y.
Solution:
Three points are collinear if:

A line contains the points R(-1, 8), S(1, 4) and T(6, y). It means, these points are collinear.



Subtract 12 from both sides.

Divide both sides by 2.


Therefore, the value of y is -6.
Answer:
Variance = 1,227.27
Standard deviation = 35.03
Step-by-step explanation:
To calculate these, we use the following formulas:
Mean = (sum of the values) / n
Variance = ((Σ(x - mean)^2) / (n - 1)
Standard deviation = Variance^0.5
Where;
n = number of values = 20
x = each value
Therefore, we have:
Sum of the values = 29 + 32 + 36 + 40 + 58 + 67 + 68 + 69 + 76 + 86 + 87 + 95 + 96 + 96 + 99 + 106 + 112 + 127 + 145 + 150 = 1,674
Mean = 1,674 / 20 = 83.70
Variance = ((29-83.70)^2 + (32-83.70)^2 + (36-83.70)^2 + (40-83.70)^2 + (58-83.70)^2 + (67-83.70)^2 + (68-83.70)^2 + (69-83.70)^2 + (76-83.70)^2 + (86-83.70)^2 + (87-83.70)^2 + (95-83.70)^2 + (96-83.70)^2 + (96-83.70)^2 + (99-83.70)^2 + (106-83.70)^2 + (112-83.70)^2 + (127-83.70)^2 + (145-83.70)^2 + (150-83.70)^2) / (20 - 1) = 23,318.20 / 19 = 1,227.27
Standard deviation = 1,227.27^0.5 = 35.03
Answer:
So 55% of an unknown number is 1452
Let this unknown number be n
Then 55% of n = 1452
We now solve for n
55% × n = 1452
55/100 × n = 1452
0.55 × n = 1452
n = 1452/0.55
n = 2640
Therefore there are 2640 students in the college