A group of persons, 55 enjoy going to the movies, 53 enjoy solving physics problems and 41 enjoy reading novels. Of these, 8 persons like all three activities, while 59 like only one of them. Then, how many persons like only two of the three activities?
A group of persons, 55 enjoy going to the movies, 53 enjoy solving physics problems and 41 enjoy reading novels. Of these, 8 persons like all three activities, while 59 like only one of them. Then, how many persons like only two of the three activities? Correct Answer 33
Given:
Person who enjoy going to movies = 55
Person who enjoy solving physics problems = 53
Person who enjoy reading novels = 41
Person who enjoy all three activities = 8
Person who like only one of them = 59
Concept:
Venn Diagram
Calculation:
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Given, X + Y + Z = 59
According to question –
⇒ X + a + 8 + b = 55
⇒ X + (a + b) = 47 ---- (i)
⇒ Y + a + c + 8 = 53
⇒ Y + (a + c) = 45 ----- (ii)
⇒ Z + (b + c + 8) = 41
⇒ Z + (b + c) = 33 ---- (iii)
Add (i) + (ii) + (iii), we get –
⇒ (X + Y + Z) + 2(a + b + c) = (47 + 45 + 33)
⇒ 59 + 2(a + b + c) = 125
⇒ 2(a + b + c) = 125 – 59
⇒ 2(a + b + c) = 66
⇒ a + b + c = 33
∴ Persons like only two of the three activities = 33