Answer:
50% or 1/2
Step-by-step explanation:
The probability of their 6th child being a girl would be 50% or 1/2.
During meiosis, the female produces X eggs while the male produces X and Y sperms. A random fusion of gametes then occurs during fertilization.
XX x XY
XX (female) XY (male) XX (female) XY (male)
XX - 1/2 or 50%
XY - 1/2 or 50%
Hence, the probability of producing a girl is 1/2 or 50% irrespective of the number of kids a couple might have produced already.