Math 250 . of Statistics (09.2017) Quiz: Quiz 2 (Ch. 7-9) 612 This Question: 1 p

Question

Math 250 . of Statistics (09.2017) Quiz: Quiz 2 (Ch. 7-9) 612 This Question: 1 pt 13 of 13 (10 wants to estimate the proportion of citizens who %llow professional football . Complete parts (a) through (c) (a) What sample size should be obtained if he wants to be within 3 percentage points with 5%confidence if he uses an estimate of 54% obtained hom a poll? The sample size is (Round up to the nearest integer) what sample size should be obtained if he wants to be within 3 percentage points with 95% confidence if ho does not use any pr or estimates? The sample size is . (Round up to the nearest integer) (c) Why are the results from parts (a) and (b) so close? A. The results are close because the confidence 95% is close to 100% O B. The results are close because the margin of error 3% is less than 5%. O C. The results are close because 0.54(1-0.54)- 0.2484 is very close to 0 25 at

Explanation / Answer

a) Critical value is 1.96.

n = 0.54(1 - 0.54) (1.96/.03)^2.

= 0.2484 * 4268.44

The answer is 1060.28~ 1061

b) Critical value is same as above; 1.96.

.25(1.96/.03)^2 = 1067.1

c) The correct option is c

The results are close because .54(1 - .54) = .2484 is very close to .25

Related Questions

Navigate

• Browse (All)
• Browse M
• Subjects

---