Given:
Number of mails received a day = 55
Spam mails = 12
Alex opens 6 emails at random.
Number of emails that are not spam = 55 - 12 = 43
The probability that none of the emails are spam is:
[tex]P\text{ = }\frac{^{43}C_6}{^{55}C_6}[/tex]Solving further, we have:
[tex]P\text{ = }\frac{6096454}{28989675}\text{ = 0.210}[/tex]Therefore, the probabilty that none of the emails are spam is 0.210
ANSWER:
0.210
