Classify the hypothesis test as two-tailed, left-tailed, or right-tailed. At one school, the average amount of time that tenth-graders spend watching television each week is hours. The principal introduces a campaign to encourage the students to watch less television. One year later, the principal wants to perform a hypothesis test to determine whether the average amount of time spent watching television per week has decreased from the previous mean of 21.6 hours.

a. Two-tailed
b. Right-tailed
c. Left-tailed

C: left tailed

Step-by-step explanation:

In two tailed hypothesis, the alternative hypothesis is when mean can either be lesser or greater than the given value. Usually uses the symbol ≠.

In right tailed, the alternative hypothesis is when the mean is greater than the given value.

In left tailed, the alternative hypothesis is when the mean is lesser than the given value.

In this question, the hypothesis test to be performed is to determine if the average amount of time spent watching television per week has decreased from the given value of 21.6 hours.

Thus, it is left tailed test.

let x be the money she spent so that she can earn the free t-shirt.

since, she already spent $112.49

⇒

also, as per the statement: jennifer must spend $250 or more in order to qualify for a free t-shirt at the store.

then,

we have an inequality i.,e

subtract 112.49 from both sides we get;

therefore, $137. 51 more money does jennifer need to spend so that she can earn the free t-shirt