Homework Answers

Rio's company is manufacturing steel wire with an average tensile strength of 50 kilos. The Laboratory test 16 pieces showed that the mean was 45kls with standard deviation of 5 kilos , is it correct to the company to claim that the tensile strength of steel wire is 50 kilos? Test the hypothesis at 0.01 level of significance.

Problem 3

A teacher wants to test his assumption that less than 30% of the Senior High School students like research class. After randomly collecting 150 samples, he found out that only 50 students like their research class.

Hypothesized proportion (p̂), th value of q, and finally the value of z.

*

p̂ = 0.27, q = 0.9, z = 2.05

p̂ = 0.27, q = 0.8, z = 2.14

p̂ = 0.27, q = 0.8, z = 2.0412

p̂ = 0.33, q = 0.7, z = 0.8

Problem 2

The Senior High School researchers claim that 20% of Senior High School male students have tried smoking cigarette. After collecting 150 random samples, they found 40 of them have tried smoking cigarette.

Hypothesized proportion (p̂), th value of q, and finally the value of z.

*

p̂ = 0.27, q = 0.9, z = 2.05

p̂ = 0.27, q = 0.8, z = 2.14

p̂ = 0.27, q = 0.8, z = 2.0412

p̂ = 0.33, q = 0.7, z = 0.8

Problem 1

A student researcher claims that 8% of the Junior High School completers will enroll in private Senior High Schools. To test this claim, he collected sufficient samples randomly and found out that 85 out of 380 Junior High School completers are planning to enroll in private Senior High Schools.

Hypothesized proportion (p̂), th value of q, and finally the value of z.

*

p̂ = 0.43, q = 0.98, z = 20.45

p̂ = 0.22, q = 0.42, z = 10.45

p̂ = 0.60, q = 0.92, z = 11.45

p̂ = 0.22, q = 0.92, z = 10.05

p̂ = 0.22, q = 0.92, z = 10.324