Probability (1 Viewer)

[chewy123]

Please help

A set if 100 cards numbered 1 to 100 is placed in a box and one drawn at random. Find the probability that the card chosen will be odd or less than 30.

 

[PC]

n(odd) = 50
n(<30) = 29
n(odd AND <30) = 15

.: P(odd OR <30) = P(odd) + P(<30) – P(odd AND <30)
= (50 + 29 – 15)/100
= 64/100
= 16/25

 

[chewy123]

n(odd) = 50
n(<30) = 29
n(odd AND <30) = 15

.: P(odd OR <30) = P(odd) + P(<30) – P(odd AND <30)
= (50 + 29 – 15)/100
= 64/100
= 16/25

Thx, but how do you find n(odd AND <30)

 

[lolokay]

Thx, but how do you find n(odd AND <30)

it's just the number of odd numbers between 1 and 30 (which is 30/2)

 

[chewy123]

I see, but is there a formula? n( A & B)?