The total measure of the interior angles of each figure will be:
180 (n-2) = 180 (4 - 2) = 360
Now add all those angles and set them equal to 360.
41 + 133 + 86 + x = 360
x is the unknown angle.
260 + x = 360
x = 100
The missing angle that is Not labeled in any of the figure is 100°
Hope this helps :)
The midsegment theorem says that the midsegment is half the third side and parallel as well. 20*2 is 40 so x = 35
One month = 5000
Number of months before the spark plugs need to change :
15000 ÷ 5000 = 3
The sparks can last 3 months before it needs to be changed.
Number of times it need to change in a year = 12 ÷ 3 = 4
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Answer : It needs to be change 4 times a year.
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The fraction 4/6 could represent the green