Answer:
(i) The student who weighed the rock 20 times.
Step-by-step explanation:
The margin of error of a confidence interval is:

In which z is related to the confidence level,
is the standard deviation of the population and n is the size of the sample.
From the equation above, the larger the size of the sample, the lower the margin is, that is, the narrower the interval is.
In this question:
A student weighed the rock 20 times and other the 5. From above, the one who weighed the rock 20 times will have the more precise interval.
So the correct answer is:
(i) The student who weighed the rock 20 times.
Answer:
See explanation below
Step-by-step explanation:
<u>First we will solve the radical equation</u> (which I guess was problem 1),
Let's start by simplifying it:

Now we will solve the equation by squaring both sides of the equation:

So the calculation for x was that x = -10
However, this does not produce a solution to the equation: When we plug this value into the radical equation we get:

This happens because <u>when we first squared both sides of the equation in the first part of the problem we missed one value for x </u>(remember that all roots have 2 answers, a positive one and a negative one) while squares are always positive.
When we squared the root, we missed one value for x and that is why the calculation does not produce a solution to the equation.
Answer:
Check pdf
Step-by-step explanation:
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