Ted works in the digital acquisitions department of the vindale public library. the library is looking into switching some of its holdings to a digital format. as part of a preliminary study, ted randomly choose 150 books from the library's collection and found and 73 of them are available is e-books. estimate the proportion of the library's collection that are available as e-books. including a margin of error.

c. 48.67% ± 8.16%

Step-by-step explanation:

The proportion is:

p = 73 / 150 = 0.4867

The margin of error is:

ME = z √(p (1 − p) / n)

where z is the critical value, p is the proportion, and n is the sample size.

For a 95% confidence interval, z ≈ 2.

ME = 2 √(0.4867 (1 − 0.4867) / 150)

ME = 0.0816

So the proportion is 48.67% ± 8.16%.

c. 48.67% ± 8.16%

Step-by-step explanation:

Ted Works in the digital Acquisitions Department of the Vindale Public Library. The library is looking into switching some of its Holdings to a digital format. As part of a preliminary study, Ted randomly choose 150 books from the library's collection and found and 73 of them are available is e-books. Therefore, estimating the proportion of the library's collection that are available as e-books. including a margin of error is 48.67% ± 8.16%.

answer: city needs 2.4 inches of rainfall more to match the record of 40 inches.

step-by-step explanation:

since we have given that

total annual rainfall a city record = 40 inches

this year, total rainfall recorded = 37.6 inches

number of inches of rainfall   is needed to match the record of 40 inches is given by

hence, city needs 2.4 inches of rainfall more to match the record of 40 inches.

x = ±sqrt(10)

step-by-step explanation:

5 - 2x² = -15

subtract 5 from each side

5-5 - 2x² = -15-5

-2x^2   = -20

divide by -2 on each side

-2x^2   /-2= -20/-2

x^2 =10

take the square root on each side

sqrt(x^2 )=±sqrt(10)

x = ±sqrt(10)

check:

5 - 2x² = -15

+sqrt(10)

5 - 2(sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15

-sqrt(10)

5 - 2(-sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15