Answer:
0.26 and 0.577
Step-by-step explanation:
Given :
x :___0 ___ 1 ____ 2 ____ 3
f(x):_0.80 _0.15__0.04 __0.01
The mean :
E(X) = Σ(x * p(x))
E(X) = (0*0.8) + (1*0.15) + (2*0.04) + (3*0.01)
E(X) = 0 + 0.15 + 0.08 + 0.03
E(X) = 0.26
Var(X) = Σx²*p(x)) - E(x)²
Σx²*p(x)) = (0^2*0.8) + (1^2*0.15) + (2^2*0.04) + (3^2*0.01) = 0.4
Σx²*p(x)) - E(x)² = 0.4 - 0.26² = 0.3324
Std(X) = √0.334 = 0.577
Answer:
sqrt239
Step-by-step explanation:
Using the pythagoream thereom, we know that a^2+b^2=c^2.
so x^2+17=256
That makes x the square root of 239.
Since there are 14 boys and the whole class has 31 students
We get, the ratio of the part-to-whole relationship for boys is 14/31.
And since there are 17 girls
We get, the ratio of the part-to-whole relationship for girls is 17/31.
Answer: 11.4%
Step-by-step explanation:
100% of your life is 57 years
?% will be 6.5 years?
this is a simple ratio problem:
57 --> 100%
6.5 ---> (6.5 x 100)/57 ≅ 11.4%
You have known the person for about 11.4% of your life.