RESEARCH METHODOLOGY

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Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
The mean life of a tire is 30, 000 km. The standard deviation is 2000 km. Then, 68% of all tires will have a life between ____ km and ____ km.
A
28, 000 km and 32, 000 km.
B
24, 000 km and 34, 000 km.
C
26, 000 km and 34, 000 km.
D
27, 000 km and 31, 000 km.
Explanation: 

Detailed explanation-1: -The mean life of a tire is 30, 000 km. The standard deviation is 2000 km. a) 68% of all tires will have a life between 28000 km and 32000 km.

Detailed explanation-2: -Key Takeaways. The Empirical Rule states that 99.7% of data observed following a normal distribution lies within 3 standard deviations of the mean. Under this rule, 68% of the data falls within one standard deviation, 95% percent within two standard deviations, and 99.7% within three standard deviations from the mean.

Detailed explanation-3: -Average tire lasts 50, 000 miles (10, 000) implies 50% of observations will last for more than 50, 000 miles (as if it follows no…

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