The perimeter of a semi-circular protractor is 72cm. Its diameter is :

(a)28cm

(b)14cm

(c)36cm

(d)24cm

ANS - 28 CM

perimeter of semi circle= pieR + 2R

R(Pie + 2) = 72

=R(36/7) = 72

R = 72 INTO 7 / 36

R = 7 X 2 = 14

DIAMETER = 14 X 2 = 28cm