8. The following pie diagram shows percentage of persons
according to blood group. Answer the following questions :
(a) Find the measure of central angle for each blood
group.
(b) Find total number of persons if there are 600 persons
of blood group B.
Sol.
a.
Blood Group
|
Percentage
|
Measure of Central angle
|
O
|
45
|
(45÷ 100)× 360 = 1620
|
A
|
20
|
(20÷ 100)× 360 = 720
|
B
|
30
|
(30÷ 100)× 360 = 1080
|
AB
|
5
|
(5÷ 100)× 360 = 180
|
Total
|
100
|
3600
|
b.
Number of persons in blood group 'B' = (30÷100) × Total Number of persons.
∴ 600 = (3/10)× Total Number of Persons.
∴ Total number of Persons = 6000/3
∴ Total number of Persons = 2000 Persons.
∴ Total numbers of persons are 2000.