Instructions: Answer the questions based on the information given below. The Venn diagram given below shows the estimated readership of 3 daily newspapers (X, Y & Z) in a city. The total readership and advertising cost for each of these papers is as below. The total population of the city is estimated to be 14 million. The common readership (in lakhs) is indicated in the given Venn diagram. The number of people (in lakhs) who read only one newspaper is
Show Hint
Subtract each paper's overlaps with the others from its total readership to get the only-one figure for that paper.
Since the previous question already gives us the count of people who read at least one newspaper, we can reach the only-one count faster by starting there and stripping away everyone who reads two or three papers, instead of recalculating each only-region from scratch.
From the Venn diagram, everyone who reads two or more papers is the sum of the three pairwise overlaps plus the centre: $2.5+1.0+1.5+0.5=5.5$ lakh.
The total who read at least one paper works out to 17.4 lakh from the totals and overlaps.
People who read exactly one paper are everyone in the at-least-one group minus those who read two or more: $17.4 - 5.5 = 11.9$ lakh.
This shortcut works because every reader falls into exactly one of two buckets, reads exactly one paper or reads two or more, and the two buckets must add up to the at-least-one total.
Let's summarize:
The number of people who read only one newspaper is 11.9 lakh, matching option B.
This cross-check also confirms the region-by-region answer was consistent.
