PS Feb 15 [9+]

What is a set ?

• Well defined collection of objects

• Collection of well defined objects

The shaded region represents

• A-B

• A U B

• B - A

• {pencil, sketch}

• {scale}

• {pen, eraser}

Match the following

• A-B

• 
• Disjoint Sets

• 
• B-A

• 
• Intersecting Sets

• 

Match the following

• {4,9,7,10,0,1,2,3,2,1010,8}

• {4,9,7}

• {12,100,14,19,55,47,1000}

• {12,100,19,55,1000,2,1010,8,47,14}

• A-B

• {1,2,3}

• B-A

Match the following

• {16,10,7,3,465,-8,1010,99}

• {8,4,-1}

• A-B

• {-1,4,98,45,0,-11,15}

• {-1,4}

• {-1,4,99}

Let A and B be two finite sets such that n(A) = 30, n(B) = 18 and n(A ∪ B) = 26, find n(A ∩ B)?

If If n(A – B) = 12, n(A ∪ B) = 45 and n(A ∩ B) = 15, then find n(B)?

In a group of 80 people, 37 like cold drinks and 52 like hot drinks and each person likes at least one of the two drinks. Find How many people like both coffee and tea?

In a school, there are 30 teachers who teach Mathematics or Physics. Of these, 18 teach Mathematics and 6 teach both Physics and Mathematics. How many teach Physics only?