(a) We know that 30% of the members of the club are female and 20% of these females own cars, and 30 female members own cars.
We can use this information to calculate the total number of female members in the club.
If 30% of the members are female and 20% of these females own cars,
then 20/100*30 female members = 6% of the total members own cars.
This means that 6% of the total members are female members who own cars.
Therefore, 30 female members / 6% = 500 female members.
So there are 500 female members in the club.
(b) If 30% of the members are female, then the total number of members is (100/30)*500 female members = 1666.67 members
(c) To increase the percentage of female members to 37.5%, we need to calculate the number of additional female members required to reach this goal. The current percentage of female members is 30% and we want to increase it to 37.5%. Therefore, we need an additional 37.5-30 = 7.5%. If the current number of female members is 500, to increase the percentage by 7.5%, we need an additional of 7.5/100*1666.67 = 125 additional female members.