# maths

posted by
**Claire** on
.

Hi Can anyone help please:

Suppose that the births of boys and girls can be modelled by rollling a fair die with 27 faces, 14 of which represent a boy and 13 represent a girl.

1. Using this model, choose the option that is closest to the probability that a couple who continue to have children until they have a boy will have exactly 3 children? I answered this as 0.1394, Is this correct?

2. Using this model, choose the option that is closest to the probability that a couple who continue to have children until they have a boy will have more than 3 children?

3. Using this model, choose the option that is closest to the probability that, in a family with five children, the 1st, 3rd and 5th are girls, while the 2nd, and 4th are boys? I got 0.03456, is this correct?

Options given for questions 1 to 3 are: A=0.0300, B=0.1116 C=0.1202 D=0.1295 E=0.1394 F=0.3221 G= 0.5469 H=06324

any help much appriciated regards Claire