Mike and Julie are making slime. The table shows the number of drops of blue food coloring and the number of drops of red food c
oloring they use in each batch Drops of Food Coloring Number of blue drops Number of red drops 20 4 40 8 60 12 80 16 What is the constant of proportionality of the ratio of the number of blue drops used to the number of red drops used? 0.2 0.5 2 5