Out of 7 children the youngest is boy then find the probability that all the remaining children are boys?

The answer mathematically speaking is 1 / 64. However, theoretically speaking each time you have a child the chances are still 50 / 50; this does not change in theory although mathematically speaking each time you have a child the chance of having another of the same sex is slightly less.

• Is this realistic?

Put into practice it is almost certain that in every 64 families that have seven children that they are not all the same sex; in fact real life the probability of this would be much lower. If you conducted research into this and surveyed all of the families in the UK with seven children, it is almost certain that you would come up with a much different number to 1 / 64.

• Why 1 / 64

The reason the mathematical answer is 1 / 64 is that there are 64 possible combinations for example one boy six girls, four girls two boys and so on. Since there are 64 possible combinations there is a 1 in 64 chance of having any one of these combinations.

• Probability

Probability is not accurate, it is just what it says, probable. For example, if you throw a dice six times it is probable that you will throw a six at some point, however you know yourself if you play Monopoly how hard it is to throw a six.

Probability works on hard figures and statistics. It works out the chances of a particular event although in real life these chances can be quite different, as other eventualities may not have been taken into account.

For example, realistically speaking if a winning lottery ticket has been purchased at your local store one week would you have less or more of a chance of winning if you purchase one there the next week? Most people think you would have less chance due to the fact that so few people win it is unlikely that in two weeks they will buy a ticket in the same location.

However, mathematically speaking the chances are exactly the same every week no matter what. This is because there are the same number of outcomes and you always put on six numbers.