Probability question.

[number1]

Please someone solve this for me. Its a book question and i only have the answer 0.061.
Here's the ques:
"It is known that 24% of the customers in a bank holding a current account also have another type of account with the bank.
Calculate an approximate value for the probability that fewer than 50 customers in a random sample of 250 customers with a current account also have another type of account."
Plz help!

 

[PlanetMaster]

Let N be the number who have another type of account.
∴N ~ binomial(250,0.24) ≈ N(60, 45.6) = N(60,6.753²) (² is square not z)
= P(N < 50) →P(N < 49.5) with continuity correction
= P(Z < (49.5 - 60)/6.753 = -1.55) = 1 - 0.93943 = 0.061

Clear?

 

[number1]

Wow!
Thnx a million times. I've been trying this since 2 days.

 

[zahraahmed]

ohhh sorrieee i did it bymistake......................

 

[filza94]

http://notezone.net/cambridgechem/chemi ... sis%5D.pdf can sum1 go in dix page 11 n do solve n gimme answers plzzzz i cant able to slove it n it might cum for exam help mee!!!!