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2 people are trying different phones to see which one has the better talk time. ChatLong has an average of 18 hours with a standard deviation of 2 hours and Talk-a-Lot has an average of 20 hours with a standard deviation of 3. The two people who tested their phones both got 20 hours of use on their phones. For the z-scores I got 1 for the ChatLong company and 0 for Talk-a-lot. What is the percentile for each z-score?

User Ziga Petek
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1 Answer

4 votes

Answer:

Explanation:

The percentile for the z scores are gotten from the normal distribution table. The z cores are already known.

1) For the ChatLong company, the z score is 0. The area corresponding to the z score from the normal distribution table is 0.5. Therefore, the percentile is

0.5 × 100 = 50%

2) For the Talk-a-lot company, the z score is 1. The area corresponding to the z score from the normal distribution table is 0.84. Therefore, the percentile is

0.84 × 100 = 84%

User Nathan
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