What will the ratio of brown eyes children to blue eye children from 2 heterozygous brown-eyed parents be?

3 to 1

______         ____  Brown   Blue
Brown _____  Brown   Brown
Blue     _______  Brown   Blue


there are four possible outcomes and the dominate trait will be shown.
sry for the messed up punnet square

This trait is made up of two alleles, B or b.  Capital B is dominant to lower-case b.  B represents the brown-eyed allele (dominant), and b represents the blue-eyed allele (recessive).

Hetero- means different, and homo- means same.  So a heterozygote would be Bb and a homozygote would be BB or bb (depending on what type of homozygote they are [brown or blue eyed]).

2 heterozygous brown eyed parents would both be Bb

Punnett squre: (parent 1 at the top and parent 2 on the side.  Since each is Bb, they can either give a B or a b to the offspring):
           B          b
B        BB        Bb

b        Bb         bb

1 child will be BB (homozygous brown), 2 children will be Bb (heterozygous brown), and 1 chidl will be bb (homozygous blue).  Therefore you will have 3 brown-eyed children (1 BB and 2 Bb's) and 1 blue-eyed child (bb).

The ratio of brown to blue will be 3:1