What is the chance of an offspring being affected with an affected mother and normal father, in an X-linked recessive condition?

Robbins basic pathology 9th edition page no 220 Here since it is an x linked recessive condition and mother is a carrier her one x is abnormal of the two x chromosome she have. And since father is unaffected he has normal x chromosome. Hence ther is a 50% chance for affected x chromosome to pass from mother to daughter. Hence 50% of the daughters will become carriers.