Mean & Proportion

In a survey of 2480 golfers, 372 said they were left-handed. The survey's margin of error was 3%. Construct a confidence interval for the proportion of left-handed golfers.

• (0.18 to 0.21)

• (0.12 to 0.18)

• (0.12 to 0.15)

• (0.11 to .19)

A survey of 280 homeless persons showed that 63 were veterans.  Construct a 90% confidence interval for the proportion of homeless persons who are veterans.

• (0.161 to .289)
• (0.176 to 0.274)
• (0.184 to 0.266)
• (0.167 to 0.283)

Tags

CCSS.HSS.IC.A.1

CCSS.HSS.IC.B.4

CCSS.HSS.ID.A.4

A random sample of 100 SAHS students found that 53 of them were in possession of a pencil. What is the p-hat for this sample?

• 0.53
• 0.5
• 0.47
• 1

The amount added and subtracted to the statistic.

• Margin of Error

• Point Estimator

• Statistic

• Population

Tags

CCSS.HSS.IC.B.4

A random sample of 150 students has a grade point average with a mean of 2.86. Assume the population standard deviation is 0.78. Construct the 98% confidence interval for the population mean.

• (2.51, 3.53)

• (2.43, 3.79)

• (2.31, 3.88)

• 2.71, 3.01)

Construct a 95% confidence interval for the population mean. Assume the population has a normal distribution. A sample of 20 college students had mean annual earnings of $3120 with a standard deviation of $677.

• ($2803, $3437)

• ($2135, $2567)

• ($2657, $2891)

• ($1324, $1567)

A random sample of 40 students has a test score with mean = 81.5. Assume the population standard deviation is 10.2. Construct the 90% confidence interval for the population mean.

• (78.8, 84.2)

• (66.3, 89.1)

• (51,8, 92.3)

• (71.8, 93.5)

Which z-value is used for a 95% confidence interval?

• 1.65
• 1.96
• 2.58
• 2.33

Tags

CCSS.HSS.ID.A.4

In a crash test of 15 troopers, collision repair costs are found to have a distribution that is approximately normal, with a mean of $1800 and a sample standard deviation of $950. Construct a 99% confidence interval for the repair cost. 

• (1069.77, 2530.23)
• (1077.13, 2522.87)
• (1167.15, 2432.85)
• None of these.

A sample of 40 people owned an average of 1.35 apple products. It is known from a previous study that the population standard deviation of apple product ownership is 0.63 products. Construct a 95% confidence interval.

• (1.11, 1.58)
• (1.15, 1.55)
• (1.19, 1.51)
• (1.09, 1.61)

Tags

CCSS.HSS.IC.A.1

CCSS.HSS.IC.B.4

CCSS.HSS.ID.A.4