## Sisters and Brothers

My daughter has as many sisters as she has brothers. Each of her brothers has twice as many sisters as brothers. How many sons and daughters do I have?

Four daughters and three sons. Each daughter has 3 sisters and 3 brothers, and each brother has 2 brothers and 4 sisters.

To figure it out mathematically, you could use the following two equations where G = the number of girls and B = the number of boys:

G – 1 = B

2(B – 1) = G

Solving for G gives you 4 and plugging that in to G – 1 = B gives you a B of 3.

Posted in Brain Teasers

8 Comments on "Sisters and Brothers"Ajay says

December 2, 2015 @ 08:12

4

Adithya says

February 21, 2016 @ 05:39

4

Chloe says

February 22, 2016 @ 06:46

3boys & 4girls ??? ?

Chloe says

February 22, 2016 @ 06:46

7

sakshi singh says

June 22, 2016 @ 06:57

Answer is 7

Mhd mhd says

July 11, 2016 @ 12:15

answer is :

2 daughters & 1 son

Dinesh Bhimsaria says

October 21, 2016 @ 03:08

One son and two daughters.

GraceyCakes says

November 23, 2016 @ 10:43

It is 4 daughters and 3 sons. It cannot be 2 daughters and 1 son because the son has to have twice as many sisters as brothers. 2*0(he has no brothers) is 0, therefore this will not work. Whereas with 4 daughters and 3 sons, one daughter will have the same amount of sisters and brothers (3), and one son will have twice as many sisters as brothers. 2*2(he has 2 brothers) is 4, the correct amount of sisters he has. Therefore, the correct amount is 4 daughters and 3 sons.

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