To calculate the <span>surface area of a composite figure you must apply the formulas for calculate the area of each figure that is part of the composite figure and then, you must sum all the areas calculated.
For example, is the composite figure is form by a triangle and rectangle, the surface area of the composite figure will be:
SA= Area of the triangle+ Area of the rectangle= (bh/2)+bh</span>
Answer:
<h3>The standard error of the mean is <u>15</u></h3>
Step-by-step explanation:
Given that a simple random sample of 64 observations was taken from a large population.
Hence it can be written as n=64
The population standard deviation is 120.
It can be written as 
The sample mean was determined to be 320.
It can be written as 
<h3>To find the standard error of the mean :</h3>
The formula for the standard error of the mean is given by
Now substitute the values in the formula we get
<h3>∴ The standard error of the mean is 15</h3>
I believe it's 1200.
Hope this helped :)
To help with thinking about this, we can say that the 6 gallons of 50% acid contains 3 gallons of pure acid and 3 gallons of filler. This would make the concentration 3/6, or 50%. Adding a gallon of pure acid would shift the concentration to 4/7, or 57.1%.
When the relationship becomes 70%, four gallons of pure acid have been added.
3+4 7
—— = — = 70%
6+4 10
Answer:
Step-by-step explanation:
It's like the same thing for adding. For example if you have 3 x 4. You can add 3 four times or you can add 4 three times. Like this.
3 + 3 + 3 + 3 = 12 because you know 3 + 3 =6 and 6 + 6 equals 12.
OR
4 + 4 + 4 = 12 because you know 4 + 4 = 8 and 8 + 4 equals 12.
I hope this helped. I am sorry if I didn't do much of help. Have a wonderful day.
