The mean that the library and calculated is not correct. Her mistake was she divided 55 by 8 instead of dividing by 10.
Please see the attached picture for the work in finding the correct mean of 5.5 books.
Answer:
x = 33
Step-by-step explanation:
these two angles are a linear pair, they form a straight line
there are 180 degrees in a straight line
so you can add each expression and have sum equal 180
2x-18 + 4x = 180
6x - 18 = 180
6x = 198
x = 33
One way is to first find the measure of one external angle:-
Measure 1 ext angle = 360 / 10 = 36 degrees (Note the sum of the external angles of all polygons is 360 degrees)
So the internal angle = 180 - 36 = 144
So sum of the internal angles
= 10 * 144
= 1440 degrees (answer)
Subtract the output from the inputs and you find that the output is the input - 4
Output = n - 4