“We – A, B and C – each have some children.
(i) A has at least one girl and twice as many boys as girls.
(ii) B has at least one girl and three times as many boys as girls.
(iii) C has at least one girl and three more boys than girls.
(iv) When I tell you the number of children we have – a number less than 25 – you will know how many children I have, but not how many children each of the others has. Altogether we have……..”
Who is the speaker and how many children does the speaker have?
(In reply to
The provided solution is incorrect - here is the correct one. by Erik O.)
No, (iii) clearly states that C must have 3 more boys than girls. Therefore, for family C:
Girls Boys Total
1 4 5
2 5 7
3 6 9 ... etc.
The problem is flawed. You can determine the speaker (A), but you cannot determine the number of children A has. It could either be 16 total children - and A has 3 OR it could be 19 total chlidren - and A has 6:
A B C Total
3 4 9 16
3 8 5 16
6 4 9 19
6 8 5 19
In any case, all you can say for sure is that A is speaking. You cannot conclude how many children A has or the total number of children.
|
|
Posted by Scott
on 2008-02-15 17:27:22 |
re: The provided solution is incorrect - here is the correct one.
