Advertisements
Advertisements
Question
A survey of 1000 farmers found that 600 grew paddy, 350 grew ragi, 280 grew corn, 120 grew paddy and ragi, 100 grew ragi and corn, 80 grew paddy and corn. If each farmer grew atleast anyone of the above three, then find the number of farmers who grew all the three.
Solution
Let P, R and C represent the set of farmers grew paddy, ragi and corn, respectively.
n(P ∪ R ∪ C) = 1000, n(P) = 600, n(R) = 350, n(C) = 280
n(P ∩ R) = 120, n(R ∩ C) = 100, n(P ∩ C) = 80
Let the number of farmers who grew all the three be “x”
n(P ∪ R ∪ C) = n(P) + n(R) + n(C) – n(P ∩ R) – n(R ∩ C) – n(P ∩ C) + n(P ∩ R ∩ C)
1000 = 600 + 350 + 280 – 120 – 100 – 80 + x
= 1230 – 300 + x
1000 = 930 + x
1000 – 930 = x
70 = x
Number of farmers who grew all the three = 70.
APPEARS IN
RELATED QUESTIONS
Write the cardinal number of the following set:
D= {3, 2, 2, 1, 3, 1, 2}
Write the cardinal number of the following set:
E = {16, 17, 18 19}
Given:
A = {Natural numbers less than 10}
B = {Letters of the word ‘PUPPET’}
C = {Squares of first four whole numbers}
D = {Odd numbers divisible by 2}.
Find: n(C)
State true or false for the following. Correct the wrong statement.
If T ={a, l, a, h, b, d, h), then n(T) = 5
In a class, all students take part in either music or drama or both. 25 students take part in music, 30 students take part in drama and 8 students take part in both music and drama. Find the total number of students in the class
In a party of 45 people, each one likes tea or coffee or both. 35 people like tea and 20 people like coffee. Find the number of people who like both tea and coffee
In a party of 45 people, each one likes tea or coffee or both. 35 people like tea and 20 people like coffee. Find the number of people who do not like tea
In a colony, 275 families buy Tamil newspaper, 150 families buy English newspaper, 45 families buy Hindi newspaper, 125 families buy Tamil and English newspaper, 17 families buy English and Hindi newspapers, 5 families buy Tamil and Hindi newspaper and 3 families buy all the three newspaper. If each family buy atleast one of these newspaper then find Number of families buy only one newspaper
If n(A ∪ B ∪ C) = 100, n(A) = 4x, n(B) = 6x, n(C) = 5x, n(A ∩ B) = 20, n(B ∩ C) = 15, n(A ∩ C) = 25 and n(A ∩ B ∩ C) = 10, then the value of x is
For any three sets A, B and C, (A – B) ∩ (B – C) is equal to