Demorgan's Law

Q.

Of the 200 candidates who were interviewed for a position at a call center, 100 had a two-wheeler, 70 had a credit card and 140 had a mobile phone. 40 of them had both two-wheeler and credit card, 30 had both credit card and mobile phone and 60 had both two wheeler and mobile phone and 10 had all three. How many candidates had none of the three?

1. 0

2. 10

3. 20

4. 18

Q. Out of 100 persons in a group, 72 persons speak English and 43 persons speak French. Each one out of 100 persons speak at least one language. Then how many speak only English ? How many speak only French ? How many of them speak English and French both ?

Q.

In a survey of 200 students from 7 different schools, 50 people do not play NFS, 40 people do not play Dota and 10 people play no online game. Then find the no. of people out of 200 people who do not play both the games provided these are the only two games on offer.

1. {3}

2. {1, 2, 3, 4}

3. {1, 2, 4, 5}

4. {1, 2, 3, 4, 5, 6}

Q.

In a survey of 300 android mobile users, who make video calls, 75 people said they use viber, 45 use skype and 90 people use both. The number of persons who use neither viber nor skype is __.

Q.

In a survey of 300 android mobile users, who make video calls, 75 people said they use only viber, 45 use only skype and 90 people use both. The number of persons who use neither viber nor skype is __.

Q.

In a survey of 300 android mobile users, who make video calls, 75 people said they use viber, 45 use skype and 90 people use both. The number of persons who use neither viber nor skype is __.