• Status: Solved
• Priority: Medium
• Security: Public
• Views: 394

# Probability of getting pregnant

OK, this is a math probability question.

We had a safety meeting this morning where a gentlemen said that he is having his third grandson after his son had a vasectomy and his son's wife had her tubes tied. A quick search says that 1/100 vasectomies will fail and 5/1000 Tubal Ligations will fail.

The question is, how do you combine the probabilites. An explanation would be awesome because I am deemed with coming up with an answer and explanation. Great...
0
wrt1mea
3 Solutions

Commented:
independent events

1 dice toss has a 1 in 6 chance of showing 1 dot 1/6

tossing 2 dice...  both resulting in 1 is 1/6 * 1/6 or 1/36 - one out of 36 throws on average...

So 1/100 * 5/1000 would be 5/100000 or 5 out of every 100000 situations where both scenarios exists... Vas and tubes tied as couple exists.

That's my take...
0

IT ConsultantCommented:
If every couple who can conceive will conceive, then the probability would be 1/100 * 1/200, or .005%.
But that is only if the vasectomy and ligation are the only factors that would prevent conception.
0

Commented:
The Probability of a failed vasectomy is 0.01.

The probability of a failed tubal ligations is: 0.005.

The combined probability of the two events together is found by multiplying the two individual probabilities.

Therefor the combined probability is: 0.01 x 0.005 =  0.00005.

[Reference (for understanding):

< http://www.ehow.com/how_8109505_combine-probability-two-events.html >]
0

Commented:
Ah, but don't forget that only 90% of couples (fertile and having regular intercourse) will be expecting a child after a year without contraception - so 0.00005 x .9 = .000045
0

IT ConsultantCommented:
You do realize that .005% means 5 in 100000, or 0.00005, don't you? :)
0

Author Commented:
Looked right over the %....crap Dan. I apologize.
0

Author Commented:
Want me to get a mod to reopen?
0

IT ConsultantCommented:
Nah, it's OK. I'll be more careful next time to skip the percentages :)
0
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.