Answer:
-72
Step-by-step explanation:
Sum is adding so I just did substitution for this. 26+-72=-46 because a positive plus a negative equals a negative.
Answer:
a) The expected number of smokers in a random sample of 140 students from this university is 16.8 smokers.
b) No, it is unlikely that smoking habits and waking up early to go to the gym on Saturday are independent.
Step-by-step explanation:
To calculate the expected numbers of smokers in a sample with size n=140 and proportion p=12%, we use the expected value of the binomial distribution:
The expected number of smokers in a random sample of 140 students from this university is 16.8 smokers.
If we take a sample at the opening of the gym, the sample is not expected to be representative of the population of the students. Most of the students that go to the gym usually have healthy habits, so the proportions of smokers is expected to be lower than the average of the university population.
If you could post the picture I can help
Answer:
r=1/π
Step-by-step explanation:
Area of the circle is defined as:
Area = πr²
Derivating both sides
=2πr
= x = 2πr
If area of an expanding circle is increasing twice as fast as its radius in linear units. then we have : =2
Therefore,
2πr = 2
r=1/π