MEDIUM
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The number of elements in set A is 30, the number of elements in the intersection of the sets A,B is 25. Find the cardinal number of the difference of the two sets A,B.

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Important Questions on Sets

EASY
If A={x|xN,x is a prime number less than 12} and B={x|xNx is factor of 10}, then AB=
MEDIUM
In a class of 140 students numbered 1 to140 , all even numbered students opted Mathematics course, those whose number is divisible by 3 opted Physics course and those whose number is divisible by 5 opted Chemistry course. Then the number of students who did not opt for any of the three courses is:
EASY
Let X=nN:1n50. If A=nX: n is a multiple of 2 and B=nX: n is a multiple of 7, then the number of elements in the smallest subset of X, containing both A and B, is.
EASY
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EASY

The shaded region in the given figure shows _____

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MEDIUM
A survey shows that 63% of the people in a city read newspaper A whereas 76% read news paper B. If  x% of the people read both the newspapers, then a possible value of x can be:
MEDIUM
Two newspapers A and B are published in a city. It is known that 25% of the city population reads A and 20% reads B while 8% reads both A and B. Further, 30% of those who read A but not B look into advertisements and 40% of those who read B but not A also look into advertisements, while 50% of those who read both A and B look into advertisements. Then the percentage of the population who look into advertisements is:
HARD
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MEDIUM
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MEDIUM
Let S=4,6,9 and T=9,10,11,,1000. If
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HARD

Let i=150Xi=i=1nYi=T, where each Xi contains 10 elements and each Yi contains 5 elements. If each element of the set T is an element of exactly 20 of sets Xi's and exactly 6 of sets Yi's then n is equal to :

MEDIUM

If A={1,2,3,4,5} and B={2,4,6}, then A-B=

MEDIUM
Consider the two sets:
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MEDIUM
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EASY
Let A and B be two sets such that AX=BX=ϕ and AX=BX for same set X. Then,
EASY
If A and B are disjoint sets, then BA', where A' is complement of A, is equal to
HARD
For any three sets A, B and C the set (ABC)AB'C''C' is equal to
EASY
If nAB=97,nAB=23 and nA-B=39, then nB is equal to
MEDIUM
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EASY
If AB, then AΔB is equal to