75/4=25 pages per hour, so, now we have to divide 250 by 25.
250/25=10
So, it would take Joan 10 hours to read 250 pages. :)
Answer:
The size of the population mean would be provided as:
mean +/- std/sqrt(sample size)
<=>
87.3 +/- 13.6/sqrt(175)
<=>
87.3 +/- 1.03
=> Option B is correct.
Hope this helps!
:)
Ruler
I have to write more so ignore this