Answer:
81.85%
Step-by-step explanation:
We have the following information:
mean = m = 52000
standard deviation = sd = 12000
a = 40000
b = 76000
we need to find the probability between a and b, that is:
P (a <x <b) = P (40,000 <x <76000)
P [(40000 - m) / sd <(x - m) / sd <(76000 - m) / sd]
replacing
P [(40000 - 52000) / 12000 <z <(76000 - 52000) / 12000]
P (-1 <z <2)
P (z <= -1) - P (z <= 2)
We look for this value of z, in the attached table:
0.9772 - 0.1587
P = 0.8185
In other words, the probability is 81.85%
Answer:

Step-by-step explanation:
1) if according to the condition a₁=3 and r=2/3, then a₁₀ can be calculated as:
a₁₀=a₁*r⁹;
2) according to the rule above:
a₁₀=3*(2/3)⁹=512*3/(6561*3)=512/6561.
Answer:

Step-by-step explanation:

Answer:
x = 20 * s / 300
Step-by-step explanation:
In this case, it is solved by means of a rule of three, that is, we know that 20 of 300 answered yes, but in the case of the strata sample, since it is a value that is not mentioned in the problem, we will assume it as " s "and the people who were selected as" x ". would:
20 x
300 s
Therefore, x:
x = 20 * s / 300
and thus they would give us the number of people that would be selected.
For example, if "s" were 240, it would be:
x = 20 * 240/300
x = 16
that is, 16 people would be selected