Prob/Stats - Lesson 4.2 Activity

What shape is the normal curve

• half curve

• bell curve

• round curve

• square curve

According to the empirical rule, how much of the data falls within 3 standard deviations? 

• 68%

• 95%

• 97%

• 99.5%

• 99.7%

In a factory, the weight of the concrete poured into a mold by a machine follows a normal distribution with a mean of 1150 pounds and a standard deviation of 22 pounds. Approximately 95% of molds filled by this machine will hold weights in what interval? 

• 1084 to 1216 pounds

• 1106 to 1150 pounds

• 1106 to 1194 pounds

• 1128 to 1172 pounds

At a local high school, GPA's are normally distributed with a mean of 2.9 and standard deviation of 0.6. What percentage of students at the high school have a GPA between 2.3 and 3.5?

• 68%

• 99.7%

• 95%

• 84%

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.

• 28,000 km and

  32,000 km

• 24,000 km and

  34,000 km

• 26,000 km and

  34,000 km

• 27,000 km and

  31,000 km

The shelf life of a particular dairy product is normally distributed with a mean of 12 days and a standard deviation of 3 days.

About what percent of the products last between 12 and 15 days?

• 68%

• 34%

• 16%

• 2.5%

• 3%

The mean GPA of students in a course at UCDavis is 3.2 with a standard deviation of 0.3. What percent of students in the course have a GPA between 2.9 and 3.8?

• 81.5%

• 47.5%

• 68%

• 95%

At a local high school, GPA's are normally distributed with a mean of 2.9 and standard deviation of 0.6. What is the GPA of the highest 2.5% of the students?

• 4.1

• 4.1 or higher

• 4.7

• 4.5 or higher

The average life expectancy of dogs is normally distributed. The mean age is 13.4 years with a standard deviation of 2.3 years.

What percent of dogs live between 11.1 and 18 years?

• 34%

• 68%

• 47.5%

• 81.5%

The birth weights of babies are normally distributed. The average weight of a baby at birth is 7.5 lbs with a standard deviation of 1lb.

What percent of babies are born between 4.5 and 8.5 lbs?

• 16%

• 34%

• 47.5%

• 84%