Question

in a couple what is the % posibility of having daughters

Answer 1

in a couple, it depends on the crossing of the genes of both of them. if there the embryo having XX chromosome then it is female and if XY chromosome then it is male. we cannot get the percentage.

Answer 2

The percentage of getting a girl child in humans is 50% as male gametes X or Y can form zygote with egg of X chromosomes. So if it is the x one it forms XX and it is a girl. If it is a Y one it forms XY and is a Boy.
Hope it helps:-)