7.The diameter of a circle is 21cm and the arc related to a sector of the circle is of degree measure 240 degree.What Is the area in sq cm of the said sector?(π=22/7) A.321 B.312 C.231 D.213
Answers (1)
So you are given a circle with radius 10.5 and a sector with 240/360 of the total area. Set up an equation:
A = πr^2 x 2/3 (I reduced the fraction in my head. Get a ruler and measure stuff until you get familiar with fractions and you can do things in your head too.)
Now punch that into your calculator and you get A = 230.9
If you take the approximation 22/7 for PI then you get 231 flat.