In a group of 40 people, 16 owned at least a phone, 7 owned only a tablet and it's known 13 owned both. What's the probability that a person, picked at random, owned neither?

40 people in total16 = at least a phone, 7 = only a tablet, 13 = both
Must figure out how many people just own a phone: 16 - 13 (both phones and tablet) = 3 (just own a phone)
So, can construct a Venn diagram to show that, of the entire group of 40, those who own either a phone or tablet break down into these categories: 3 people own only phones, 13 own both a phone and tablet, 7 own only a tablet.
3 + 13 + 7 = 23 (own a phone and/or a tablet)
Subtract this number from the total size of the group to find number of people who don't own either:40 - 23 = 17 (don't own either)
Answer:17/40

Answered by Milan R. Maths tutor

2395 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

which expression is equivalent to x^2-4? (x-2)^2 (x-2)(x+2) (x+2)(x+2) x^2(-4)


How can you find the integral of x^-1


Solve the simultaneous equation: 3x+2y=8 and 2x+5y=-2


Christine has more money than David. If Christine gave David £30, then they would have the same amount. If David gave Christine £33, then Christine would have twice as much money as David. How much money does each person have?


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo
Cookie Preferences