Question

In a pollution study of 1500 Indian canals the following data were reported. 520 were polluted by sulphur compounds, 335 polluted by phosphate 425 were polluted by crude oil, 100 were polluted by both crude oil and sulphur compounds, 180 were polluted by both sulphur compounds and phosphate, 150 were polluted by both phosphates and crude oil and 28 were polluted by sulphur compounds, phosphates and crude oil. How many of the canals were polluted by at least one of the three impurities? How many of the canals were polluted by exactly one of the three impurities?

• A. 678, 512
• B. 768, 504
• C. 916, 496
• D. 878, 504

Answer 1

The correct option is D 878, 504


Number of cannals were polluted at least one of three impurities
= 268+152+33+72+28+122+203
= 878
Also, the number of canals were polluted by exactly by one of three impurities
= 268+33+203 = 504