To decorate a cake, you make a shade of green icing using 3
3
drops of yellow food coloring for every 4
4
drops of blue food coloring. If you use 12
12
drops of yellow food coloring, how many drops of blue food coloring would you need?
You would need 16 drops of blue food coloring. The ratio of yellow to blue food coloring is 3:4. If you divide 12 by 3, you get 4. This means you must multiply the base amount of blue food coloring (4 drops) by 4 to get your answer.