Answer:
96 is the number of original women investors.
Explanation:
Let X be the number of young women in the initial group. They raised 480000, so the average payment per person was (480000/X).
When 4 pull out, the new average is (480000/(X-4)). We are told that this new average required the remaining women (X-4) to add another 20000.
The four women therefore had contributed 20000 in total, making their average 20000/4 = 5000 each.
This would have been the same amount contributed by all X women. Thus, we can set the average (480000/X) equal to 5000
(480000/X) = 5000
(480000) = 5000X
(480000)/5000 = X
X = 96
The original number of women was 96.
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Check
(96 Women)(5000/Woman) = 480000 CHECKS
(4 Women pull out)*(5000) = 20000 that needs to be added to stay at 480000. CHECKS