PLSSS ANSWER QUICK
Find the expected value and standard deviation.

1) E(X) = 1.5

2)SD = 1.118

Step-by-step explanation:

1) Formula for expected value of this set of data is;

E(X) = Σx * P(x)

Σx = 0 + 1 + 2 + 3 = 6

And P(x) = ¼

Thus;

E(X) = 6 × ¼ = 1.5

2) Formula for the standard deviation is;

SD = √Σ((x - μ)²•P(x))

Where μ is the expected value = 1.5

At x = 0,we have;

(0 - 1.5)² × 1/4 = 0.5625

At x = 1, we have;

(1 - 1.5)² × 1/4 = 0.0625

At x = 2, we have;

(2 - 1.5)² × 1/4 = 0.0625

At x = 3, we have;

(3 - 1.5)² × 1/4 = 0.5625

Thus,Σ((x - μ)²•P(x)) = 0.5625 + 0.0625 + 0.0625 + 0.5625 = 1.25

Thus;

SD = √1.25

SD = 1.118

d. bc = 12 and ef = 16

step-by-step explanation:

we are given that δabc : δdef such that .

also, it is given that

so, from the options, we need that .

a.

b.

c.  

d.

as, we can see that only option d gives the same ratio as i.e. .

hence, the possible lengths are bc = 12 and ef = 16.