Answer:
Systematic sampling
Step-by-step explanation:
An EPA contractor needing to test the concentration of a substance in ten samples out seventy samples provided form a single source at regular time intervals.
For the contractor to effectively carry out the testing he has to employ a Non-probability system of sampling which is called Systematic sampling, because in systematic sampling we can assume the population size (x ) which in this case is 70 and the sample size( n ) to be 10
He will have to select ; ( x / n )^th of the sampling frame for best results
The average density of the rod is 0.704 kg/m.
For given question,
We have been given the linear density in a rod 5 m long is 10 / x + 4 kg/m, where x is measured in meters from one end of the rod.
We need to find the
The length of rod is, L = 5 m.
The linear density of rod is, ρ = 10/( x + 4) kg/m
To find the average density we need to integrate the linear density from x₁ = 0 to x₂ = 5,
The expression for the average density is given as,
⇒ ρ'
......................(1)
Using u = x + 4
du = dx
u₁ = x₁ + 4
u₁ = 0 + 4
u₁ = 4
and
u₂ = x₂ + 4
u₂ = 5 + 4
u₂ = 9
By entering the values above into (1), we have:
⇒ ρ'
= 0.704
Thus, we can conclude that the average density of the rod is 0.704 kg/m.
Learn more about the average density here:
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9514 1404 393
Answer:
25%
Step-by-step explanation:
Apparently, we're to assume that anything not spent is saved.
Let Hideo's income be 1. Then Akira's income is 5/8. Akira's expenses are 60% = 3/5 of that value, so ...
Akira's expenses = (3/5)(5/8) = 3/8 . . . . . of Hideo's income
Hideo's expenses are twice this amount, so ...
Hideo's expenses = (2)(3/8) = 3/4 . . . . . of Hideo's income
That means Hideo saves 1 -3/4 = 1/4 = 25/100 = 25% of his income.
Hideo saves 25% of his income.
Multiply $39.79 by 8.25% (.825) = $3.28
Then add $3.28 to $39.79 = $43.07
You can make an inequality out of this: 20≥2x+10