Final answer:
To make cereal squares with 6 cups of cereal, Jamie will need 40 mini-marshmallows.
Step-by-step explanation:
To find the number of mini-marshmallows needed to mix with 6 cups of cereal, we can use the given ratio of mini-marshmallows to large marshmallows. The ratio is 3 to 1, which means for every 3 mini-marshmallows, there is 1 large marshmallow.
First, we need to find the number of large marshmallows needed. The recipe uses a ratio of 20 large marshmallows to 3 cups of cereal. So, for 6 cups of cereal, the number of large marshmallows needed would be: 20 large marshmallows / 3 cups of cereal * 6 cups of cereal = 40 large marshmallows.
Now, we can use the ratio of mini-marshmallows to large marshmallows to find the number of mini-marshmallows needed. The ratio is 3 to 1, so for every 3 large marshmallows, we need 3 mini-marshmallows. Since we need 40 large marshmallows, we would need: 40 large marshmallows / 3 large marshmallows * 3 mini-marshmallows = 40 mini-marshmallows.