Astudy claims that college students spend an average of 4 hours or less studying per day. a researcher wants to check if this claim is true. a random sample of 121 college students randomly selected and it showed that average of hours studying per day was 3.15 with a standard deviation of 1.2 hours. using the 10% significance level, can you conclude that the claim college students spend an average of 4 hours or less studying per day is valid?

Let be the population mean.

By observing the given information, we have :-

Since the alternative hypotheses is left tailed so the test is a right-tailed test.

We assume that the time spend by students per day is normally distributed.

Given : Sample size :  n=121 , since n>30 so we use z-test.

Sample mean :

Standard deviation :

Test statistic for population mean :-

Critical value (one-tailed) corresponds to the given significance level :-

Since the observed value of z (-7.79) is less than the critical value (1.2816) , so we do not reject the null hypothesis.

Hence, we conclude that we have enough evidence to accept that the college students spend an average of 4 hours or less studying per day.

let's solve your equation step-by-step.

4x+2=2x+12

step 1: subtract 2x from both sides.

4x+2−2x=2x+12−2x

2x+2=12

step 2: subtract 2 from both sides.

2x+2−2=12−2

2x=10

step 3: divide both sides by 2.

2x

2

=

10

2

x=5

step-by-step explanation:

set each factor equal to 0

4x-3 = 0

2x-1 = 0

solve for x.

4x-3=0

4x=3

x= 3/4

solve for x. 

2x-1= 0

2x= 1

x= 1/2

your answer should be 1/2 is less than or equal to x and 3/4 is greater than or equal to x