A researcher claims that Republican Party will win in next Senate elections especially in Florida State. A statistical data reported that 23% voted for Republican Party in last election. To test the claim a researcher surveyed 80 people and found 22 said they voted for Republican Party in last election.

Suppose the IQ in a population is normally distributed with a mean of μ = 100 and standard deviation of σ = 15. A scientist wants to know if a new medication affects IQ levels, so she recruits 20 patients to use it for one month and records their IQ levels at the end of the month.

The Christian population in the US is 75%. But you gathered 1,000 Americans and found out that there are 60% of them who are Christians. Do you think there is enough claim for you to say that your proportion is different?

Suppose we want to know whether or not the mean weight between two different species of turtles is equal.

Is gender independent of education level? A random sample of 395 people were surveyed and each person was asked to report the highest education level they obtained.

You are a social researcher interested in the relationship between income and happiness. You survey 500 people whose incomes range from 15k to 75k and ask them to rank their happiness on a scale from 1 to 10.

A study was conducted to investigate the effectiveness of hypnotism in reducing pain. A lower score indicates less pain. The “before” value is matched to an “after” value and the differences are calculated. The differences have a normal distribution. Are the sensory measurements, on average, lower after hypnotism? Test at a 5% significance level.

As a crop researcher, you want to test the effect of three different fertilizer mixtures on crop yield.

A genetics engineer was attempting to cross a tiger and a cheetah. She predicted a phenotypic outcome of the traits she was observing to be in the following ratio 4 stripes only: 3 spots only: 9 both stripes and spots. When the cross was performed and she counted the individuals she found 50 with stripes only, 41 with spots only and 85 with both.