The best estimate of the population means is always the sample mean. We have the sample values, using them we can find the sample mean.
The sum of the sampled rates = 248
Sample Size = 10
Mean value of the sample = Sum of Sample Rate/Sample Size
So,
Mean of the sample = 248/10 = 24.8
Therefore, we can say that the best estimate for the population mean is 24.8
Amount of chemical A mixed in medicine = 9.357 g
Amount of chemical B mixed in medicine = 12.082 g
Amount of chemical C mixed in medicine = 7.502 g
We have to determine the total amount of medicine he prepared in grams.
Total amount of medicine
= 9.357 + 12.082 + 7.502
= 28.941 grams
So, he prepared 28.941 grams of medicine.
Now, we have to round each chemical to the nearest tenth.
Amount of chemical A mixed in medicine = 9.357 g
Rounding to nearest tenth = 9.4 grams
Amount of chemical B mixed in medicine = 12.082 g
Rounding to nearest tenth = 12.1 grams
Amount of chemical C mixed in medicine = 7.502 g
Rounding to nearest tenth = 7.5 grams
Answer:
The correct option is B. The area of the figure is 40.4 units².
Step-by-step explanation:
The line AB divides the figure in two parts one is a rectangle and another is semicircle.
The distance formula is

The length of AB is

The length of AD is

Since AB=AD, therefore ABCD is a square. The area of the of square is

The area of square is 29 units².
The area of a semicircle is

Since AB is the diameter of the semicircle, therefore the radius of the semicircle is

The area of the semicircle is

The area of the figure is

Therefore the area of the figure is 40.4 units². Option B is correct.
Using a system of equations, it is found that there are 34 pop songs are on the playlist.
<h3>What is a system of equations?</h3>
A system of equations is when two or more variables are related, and equations are built to find the values of each variable.
In this problem, the variables are:
- Variable x: Number of hip-hop songs.
- Variable y: Number of pop songs.
Brandon has a playlist with 83 hip-hop and pop songs, hence:
x + y = 83.
There are 15 more hip-hop songs than pop songs, hence:
x = 15 + y.
Replacing the second onto the first equation:
x + y = 83.
15 + y + y = 83.
2y = 68.
y = 34.
There are 34 pop songs are on the playlist.
More can be learned about a system of equations at brainly.com/question/24342899
Her work is incorrect because she accidentally changed -14 to -7 in the second step.
Working it out from the top we get
(x-14)+11=x-(x-4)
x-14+11=x-x+4
x-3=0+4
Final answer:
x=7
Hope I helped :)