Question

Can some one explain how to solve this?

Answer 1

This is what i have so far.

Answer 2

For (c), you need to find the total number of multiple births for all categories of women less than 45 years old... this appears to be every category except the last category, 45-54.

Then compare that sum with the total for all categories.

This should end up like (sum for all categories - 119) / (sum for all categories) since 119 is the number for the oldest category.

Answer 3

Ok I got 0.984

Answer 4

Me too. Good work :)

(D) is similar... "at least 20 years old" means count all multiple births for any category in which the mother is at least 20... so it appears to include all but the youngest category.

Compare that sum to the total...

Answer 5

so i do 7414-91/7414?

Answer 6

yes :)

Answer 7

the approach in general is: find the number of "events" (in this case, "multiple births") that meet the condition. If it's a single age group, it's just the births in that group. But if it is a range of ages, just add all the births in that range. It could be two categories, all but 1, the middle 5 categories, whatever... just add the ones that meet the condition in the problem.

Once you have the births that meet the condition, the probability is that number divided by the total number of births.

Answer 8

so would it be 0.988?

Answer 9

yes, that's what I got too :) Nice work again :) Does it make sense now?

Answer 10

Yah THX!!!

Answer 11

Great! Glad to help!