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Unit 7: Quiz Unit 7: Quiz Quiz: Unit 7: Quiz 4) 10 of 10 (8 complete) in an expe

ID: 3057191 • Letter: U

Question

Unit 7: Quiz Unit 7: Quiz Quiz: Unit 7: Quiz 4) 10 of 10 (8 complete) in an experiment to test their abilily o determine minute winds Ama ing 0a1e . 8 8 seconh construct and interpret a 99% corhence interval estinute of the This Quiz: 20 pts whon one minude (or sixty seconds) has passed Forty students yielded a sample mean of 623 ormal distribution table distribution table population mean of all students igers or decinals rounded to one decimal place as needed) d the renut i t ly Phat the students estimates have a mean that is reasonably close to Ne becase he conidence interval includes sity seconds O D. Ye becae the cdence interval includes sisty seconds

Explanation / Answer

Solution:

We use z test here, since sample size is greater than 40. Also is known.

= 8.8

sample mean= x bar = 62.3

= 1% or 0.01

/2= 5% = 0.005

Z/2 = 2.57

Interval will be,

x-bar - Z/2./n < < x-bar + Z/2./n

62.3 - 2.57(8.8/40)< < 62.3 + 2.57(8.8/40)
62.3 -3.5759 < < 62.3 + 3.5759
58.72 < < 65.88

We can say that at 99%, lies between 58.72 and 65.88

So it is likely that students estimates have a mean that is reaonably close to 60 seconds.