Answer:
39 investors contributed $6,000, and 21 investors contributed $12,000.
Step-by-step explanation:
Let's say that x investors contributed $6,000, and y investors contributed $12,000.
x + y = 60
6,000x + 12,000y = 486,000
x + 2y = 81
x + y = 60
y = 21
x + 21 = 60
x = 39
So, 39 investors contributed $6,000, and 21 investors contributed $12,000.
Hope this helps!