Question

In a group of 100 people, 70 read Sama patra and 60 read Patrika,

find how many of them

read both newspaper
only one newspaper​

Answer 1

• 30 people read both newspapers,
• 70 people read only one newspaper.

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Use the principle of inclusion-exclusion.

Substitute values and find the number of Both:

• Total readers = Sum of Each - Both
• Total readers = 70 + 60 - Both
• 100 = 130 - Both
• Both = 130 - 100
• Both = 30

Find out how many read only one newspaper:

• Only one = Total - Both
• Only one = 100 - 30
• Only one = 70

So, 30 people read both newspapers, and 70 people read only one newspaper.