Answer: 30 ml of yellow pigment & 18 ml of red pigment
Step-by-step explanation: Your trying to make the color pastel orange and to do that, you need 5 ml of yellow and 3 ml of red with 1 litre of white.
In the problem, you are using 6 litre of white to make the same color. 6 is 6 times the original amount of white you use to make pastel orange so you multiply 6 to both the other colors.
I hope it was correct.