Why is the frequency of red-green colour blindness is many times higher in males than that in the females?

Colour blindness is common hereditary condition which means it is passed down from parents. Red/green colour blindness is passed from mother to son on the 23^rd chromosome, which is known as the sex chromosome. The faulty gene for colour blindness is found only on the X chromosome. When the father is colour blind, he can only pass an X chromosome to his daughter. Thus she acquires the gene and become the carrier of the disease. While a mother who can pass the X chromosome to both son and daughter. For a son to be colour blind, it is enough for his mother to be a carrier. But for a daughter to be colour blind her father should be colour blind and mother who is a carrier of colour blindgene. For a daughter to be a carrier it is enough to get the faulty gene from carrier mother or colour blind father.

Thus males have higher frequency to be colour blind than females.