If 6 out of the first 10 people were wearing baseball caps, then the proportion of people wearing baseball caps is 6/10. To find out how many people out of 600 would be wearing baseball caps, you can set up a proportion:
(6/10) = x/600
To solve for x (the number of people wearing baseball caps), you can cross multiply:
10x = 6 x 600
10x = 3600
Now, divide both sides by 10 to solve for x:
x = 3600 / 10
x = 360
So, if 600 people were in line, approximately 360 of them would be wearing baseball caps.