Answer:
42 minutes.
Step-by-step explanation:
We know that:
y = 0.2*x
is the equation that that defines the distance, in miles, that the boat travels in x minutes.
We know that the dolphins are at 8.4 miles from the boat.
Then when we have y = 8.4, this will mean that the boat reached the dolphins.
Then we need to solve the equation:
y = 8.4 = 0.2*x
for x
To do that, we just need to isolate x in one side of the equation, so we can just divide both sides by 0.2 to get:
8.4/0.2 = (0.2*x)/0.2
42 = x
And x is time in minutes, thus, the boat needs to travel for 42 minutes to reach the dolphins.
Answer:
1.635
Step-by-step explanation:
Answer:
d. The population standard deviation is known.
Step-by-step explanation:
T-distribution or Z-distribution, which to use?
If we have the population standard deviation is known, we use the z-distribution.
Otherwise, if we only have the standard deviation for the sample, we use the t-distribution.
Which of the following is not appropriate to use the t-confidence interval for
When the population standard deviation is known, so letter d.
