Answer:
32/9
Step-by-step explanation:
Answer:
b. The margin of error would decrease.
Step-by-step explanation:
Margin of error of a confidence interval:
The margin of error of a confidence interval has the following format:

In which z is related to the confidence level,
is the standard deviation of the population and n is the size of the sample.
This means that the margin of error is inversely proportional to the size of the sample, which means that if the sample size increases, the margin of error decreases.
In this question, the sample size is increased, leading to a smaller margin of error. So the correct answer is given by option b.
The two quadrilaterals are given similar .
In any similar figure sides are in proportion.The second largest side of quadrilateral ABCD is 16 ft .Let the second longest side of quadrilateral EFGH be x ft. These sides will be in proportion to each other .
The second shortest side of quadrilateral EFGH that is GF will be proportional to the third longest side of quadrilateral ABCD that is BC
We can form a proportion with the proportional sides:

To solve for x we cross multiply
12x=(16)(18)
12x=288
Dividing both sides by 12 we get
x=24.
The second longest side of quadrilateral EFGH is 24 ft.
Answer:
Age= 15
Step-by-step explanation:
Let a be for age at the moment
(a-3)^2 =6(a+9)
a^2-6a+9=6a+54
a^2-12a-45
(a-15)(a+3)
a=15 or a=-3
Age cannot be negative (-)
Therefore
Age =15
Time = Distance / speed
Time = 20 miles / 12mph
Time = 1 and 2/3 hours ( 1 hour and 40 minutes)