Mathematics Question and Solution
Notice.
Three Congruent Half Circles With Area 72 cm² Each.
Calculating Area Blue.
Calculating r, Radius of the half circle.
½(22/7)r² = 72
Where π = 22/7
(11/7)r² = 72
11r² = 504
r = √(504/11)
r = 6.76891289781 cm.
a = 2(60π*6.76891289781²/360)-(½(6.76891289781)²sin60)
a = 28.1408330954 cm²
b = 60-20
b = 40°
c = (40π*6.76891289781²÷360)+(60π*6.76891289781²÷360)-(0.5*6.76891289781²sin60)
c = 20.1440517953 cm²
It implies;
Area Blue is;
a-c
= 28.1408330954-20.1440517953
= 7.9967813001
= 8 cm²
