Answer:
24 females with unlisted phone numbers
Step-by-step explanation:
20% of the staff at this hospital have unlisted telephone numbers
40% of the staff at the hospital that have unlisted telephone numbers are females
This means that 40% of the 20% of the 300 names in the phone book will be females with unlisted phone numbers.
1/5 (20%) of 300 is 60, and 40% of these 60 people is 24.
There are 24 females in this 300 with unlisted phone numbers.
I'm not entirely sure if this is what you were asking, since you had some errors in your question.