An SRS of size 100 is taken from a population having proportion 0.7 successes. An independent SRS of size 200 is taken from a population having proportion 0.3 successes. The sampling distribution for the difference in sample proportions has what standard deviation?

μ = 0.4

Standard deviation σ = 0.0512 (Approx)

Step-by-step explanation:

Given:

Sample size n1 = 100

Sample size n2 = 200

Proportion p1 = 0.7

Proportion p2 = 0.3

Find:

Standard deviation σ

Computation:

μ = p2 - p1

μ = 0.7 - 0.3

μ = 0.4

Standard deviation σ = √p1(1-p1)/n1 + p2(1-p2)/n2

Standard deviation σ = √0.7(1-0.7)/100 + 0.3(1-0.3)/400

Standard deviation σ = √0.0021 + 0.000525

Standard deviation σ = √0.002625

Standard deviation σ = 0.0512 (Approx)

d. millimeters per hour.

step-by-step explanation:

we are given that,

carlo used a rain gauge to measure the amount of water his lawn is receiving from the sprinklers.

since, according to the options, we see that,

water cannot be measured by 'miles per hour', 'meters per second' and 'grams per seconds'.

we get that, the water can be measured by 'millimeters per hour'.

hence, the appropriate rate for describing the amount of water is 'millimeters per hour'.

the answer is a

step-by-step explanation: