Answer:
The standard deviation of this probability distribution is 1.2.
Step-by-step explanation:
We have that:
P(X = 0) = 0.25
P(X = 1) = 0.3
P(X = 2) = 0.1
P(X = 3) = 0.35
Mean:
Each value multiplied by its probability. So
Variance:
Sum of the squares of the values subtracted from the mean, and multiplied by its probability.
Standard deviation:
Square root of the variance. So
The standard deviation of this probability distribution is 1.2.
Answer:
The amount of white fabric to coloured fabric as a ratio is 20:11
Step-by-step explanation:
We are given that For each 11 mm of colored fabric Nick uses to make his curtains, he also uses 2 cm of white fabric.
Length of colored fabric = 11 mm
Length of White fabric = 2 cm
1 cm = 10 mm
2 cm = 20 mm
So, length of white fabric = 20 mm
So, Ratio of the amount of white fabric to coloured fabric =
Hence the amount of white fabric to coloured fabric as a ratio is 20:11