Find the probability at least 3 children do not recognize their ...

[kamilo84]

Find the probability at least 3 children do not recognize their mother's voice.
 
  What will be an ideal response?

Question 2

What is the probability that both man and woman are working?
 
  What will be an ideal response?

[Viet Thy]

Answer to Question 1

P(X  3 ) = 0.323 (Here P = 0.10 )

Answer to Question 2

P(both man and woman are not working) = 1 - .88 = 0.12
P(woman doesn't work  man doesn't work) = 0.40
P(man does not work) = P(both man and woman are not working) / 0.40
= 0.12 / 0.40 = 0.30
P(man does not work) = P(man doesn't work and woman doesn't work)+
P(man doesn't work and woman works)
Then, 0.30 = 0.12 + P(man doesn't work and woman works)
Hence, P(man doesn't work and woman works) = 0.30 - 0.12 = 0.18
P(woman does work) = P(woman works and man works) +
P(woman works and man does not work)
Then, 0.40 = P(woman works and man works) + 0.18
Hence, P(woman works and man works) = 0.40 - 0.18 = 0.22

[kamilo84]

Gracias!

[chereeb]

Wow, this really help