<span>a) We know that the correct answer will be the square root of 256 since the competition area is a square with an area of 256 meters. And since 10^2 = 100 which is less than 256, the answer has to be greater than 10. And since 20^2 = 400 which is greater than 256, the answer also has to be less than 20. Therefore the answer has to be between 10 and 20.
b) The last digit has to be either a 4 or a 6. The units digit is the only digit that will contribute to the units digit of the square. And 0^2 = 0, 1^2 = 1, 2^2 = 4, 3^2 = 9, 4^2 = 16, 5^2 = 25, 6^2 = 36, 7^2 = 49, 8^2 = 64, 9^2 = 81. Of the 10 possible digits, only the values 4 and 6 have a square that has an units digit of 6.
c) The square root of 256 based up (a) and (b) above has to be either 14, or 16. So the dimensions are either 14x14 meters or 16x16 meters.</span>
Answer:
Step-by-step expla2nation:
Answer:
Horizontal distance between lifeguard and the person is 22 feet.
Step-by-step explanation:
Given: A lifeguard sees a person in distress.The eye level of the lifeguard is 15 feet above the ground. Angle of depression is 34°.
To find: Horizontal distance between lifeguard and the person.
Solution : If we draw a triangle then tan∅ = 
Here base is the horizontal distance.
Now we put the values in the formula.
tan 34° = 
Or Base = 
= 
So the answer is 22 feet.
Answer:
A sample size of 79 is needed.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.
In which
z is the zscore that has a pvalue of
.
For this problem, we have that:

The margin of error is:
95% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
What sample size is needed if the research firm's goal is to estimate the current proportion of homes with a stay-at-home parent in which the father is the stay-at-home parent with a margin of error of 0.09?
A sample size of n is needed.
n is found when M = 0.09. So






Rounding up to the nearest whole number.
A sample size of 79 is needed.