Answer:
%35 of them were in color
Step-by-step explanation:
Since 30 percent of the first 200 sold were in color, 200x30/100 = 60 of them were in color.
Since 20 percent of the next 300 sold were in color, 300x20/100 = 60 of them were in color.
Since 90 percent of the last 100 sold were in color, 100x90/100 = 90 of them were in color.
In total, 60 + 60 + 90 = 210 out of 600 were in color.
The percentage is: = → x = = 35