Answer: True.
Step-by-step explanation:
Let [tex]\mu[/tex] be the population mean.
Given : Null hypothesis = [tex]H_0:\mu=160[/tex]
Alternative hypothesis =[tex]H_1:\mu<160[/tex]
Since , the alternative hypothesis is left-tailed, then the test is a left-tailed test.
The sample mean ([tex]\overlien{x}[/tex]) of the 80 students who were weighed was found to be 142 pounds and the p-value was 0.03.
We know that p-value gives that probability that if the null hypothesis is true, than the sample mean ([tex]\overlien{x}[/tex]) will be at least as small as the actual mean ([tex]\mu[/tex]).
It means that if the mean of all students’ weight is 160 lbs, then there would be only a 3% chance that a randomly selected group of 80 students would have a mean weight of less than 142 lbs.
Hence, the answer is "True".