Answer:
6224 Brand X residents and 9335 Brand Y residents
Step-by-step explanation:
Total number of residents in the survey=15559
Residents that prefer Brand X=40%
Residents that prefer Brand Y=60%
<u>Population sample?</u>
Residents that prefer Brand X= 40/100 ×15559 =6223.6⇒6224 residents
Residents that prefer Brand Y= 60/100 × 15559 =9335.4⇒⇒9335 residents
1.666666666666667 to be exact, but rounded it is 1.66
Mean diameter = 25 mm
Standard deviation = 0.2 mm
25.6 mm - 25 mm = 0.6 mm
0.6 mm : 0.2 mm = 3
Answer:
A ball bearing with a diameter 25.6 mm differs from the mean
D ) 3 standard deviations.