Answer: true
Step-by-step explanation:
Z-tests are statistical calculations that can be used to compare the population mean to a sample mean The z-score is used to tellsbhow far in standard deviations a data point is from the mean of the data set. z-test compares a sample to a defined population and is typically used for dealing with problems relating to large samples (n > 30). Z-tests can also be used to test a hypothesis. Z-test is most useful when the standard deviation is known.
Like z-tests, t-tests are used to test a hypothesis, but a t-test asks whether a difference between the means of two groups is not likely to have occurred because of random chance. Usually, t-tests are used when dealing with problems with a small sample size (n < 30).
Both tests (z-tests and t-tests) are used in data with normal distribution (a sample data or population data that is evenly distributed around the mean).
Answer:

Step-by-step explanation:
hope this helps.
Answer:
80 lemons
Step-by-step explanation:
Let x represent the amount of lemons that were on the tree.
We can use this to set up an equation:

Note that percentages can also be written as that number over 100.

Simplify the fraction.

Multiply both sides by 5

Divide both sides by 2

There were 80 lemons on the tree before he picked the lemons.
Answer:
y=-3
Step-by-step explanation: