147k views
2 votes
The distribution of the amount of money spent by students for textbooks in a semester is approximately normal in shape with a mean of $235 and a standard deviation of $20. According to the standard deviation rule, how much did almost all (99.7%) of the students spend on textbooks in a semester?

1 Answer

2 votes

Answer: $295

Step-by-step explanation:

Given that,

Amount spent by the students is normal in shape

Mean = $235

Standard deviation = $20

99.7% is within 3 standard deviations of the mean:

= Mean + 3 × Standard deviation

= $235 + 3 × $20

= $235 + $60

= $295

The amount of $295 is spent by all the students on textbooks.

User Minamijoyo
by
7.3k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories