Answer:
60
Explanation:
Let x = number of people at the party.
0.9x wore red dresses.
2/25x wore green dresses.
rest of people wore white dresses
The rest of the people is
x - 0.9x - 2/25 x
x - 0.9x - 0.08x = 15
0.02x = 15
x = 750
0.9x = 675 (red)
2/25 x = 60 (green)
0.02x = 15 (white)
Answer: 60