Question

#14-8: A sack contains only purple, green, and yellow beads. If selected at random, the P(purple)= 1/5 and P(green)= 1/10. What is the probability of selecting a yellow bead? Express the probability as a number between 0 and 1.

Answer 1

P(yellow) =
`(7)/(10)`

Explanation:

A sack contains: Purple, Green and Yellow beads

If selected at random;

P(purple) =
`(1)/(5)`

P(green) =
`(1)/(10)`

P(yellow) = x

P(purple) + P(green) + P(yellow) = 1

i.e
`(1)/(5)` +
`(1)/(10)` + x = 1

x = 1 - (
`(1)/(5)` +
`(1)/(10)`) =
`(7)/(10)`

Answer 2

0.7

Explanation:

The way to solve this is to subtract the two fractions from 1.

P(y) = 1 - (1/5 + 1/10)

P(y) = 1 - (2/10 + 1/10)

P(y) = 1 - (3/10)

P(y) = 7/10

7/10 = 0.7