Answer:
Mean = 30
standard Deviation = 2.74
Step-by-step explanation:
Formula
mean = np
Standard Deviation = 
from the question = 40
P = 75% or 0.75
q = 1 - p = 1 - 75% or 1 - 0.75
To find mean
mean = 40 x 0.75
= 30
For Standard Deviation (SD)
Standard Deviation =
= 
= 
:. Standard Deviation = 2.74
If it takes him 90 minutes to read 5 and a half chapters, it would take him 16.36 minutes to read one chapter.
At the beginning it was 22 inches below normal (-22).
Then it decreased by 3 1/6 (-19/6).
Then increased by 1 6/7 (+13/7)
-22 - 19/6 + 13/7
-924/42 - 133/42 + 78/42
-1057/42 + 78/42
-979/42
-23 13/42
It was 23 13/42 inches below normal after April.
Elimination
A, they are both linear
linear equations are sometimes given by y=mx+b, equation A, if graphed, produces a hyperbola which is not linear so statement A is false
B they areboth non-linear
equationb is linear so this is false
C equation a is non-linear and equation b is linear
true
C is the answer