Question

A packet of juice mix makes 21 fluid ounces of juice when mixed with 3 quarts of water. What is the unit rate? How much water will be needed if the packet makes 49 fluid ounces

Answer 1

To convert this to a unit rate, both juice and water need to be in the same units

imo it's easier to go from quarts to fluid oz. than the other way around.

3 quarts * (4 cups/quart) * (8 fluid oz/1 cup) = 96 fluid oz of water

from there, the unit rate is simply 21 fluid oz juice/96 fluid oz of water ---> simplify

Answer 2

for the second part:

How much water will be needed if the packet makes 49 fluid ounces?

we can set up a proportion

(21 fluid oz juice/96 fl oz water) = (49 fluid oz of juice) / (x fluid oz of water) and solve for x