
First let's find out how much cups is in 2 gallons.
1 gallon ==> 16 cups
2 gallons ==> 32 cups
So,

Now, 5 times what equals 32??
5 × 6.4 = 32
So therefore, we must also multiply 1.5 by 6.4.
1.5 × 6.4 = 9.6
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Answer : 9.6 cups of lemon juice are needed for 2 gallons of lemonade.
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I hope that helps you out!!
Any more questions, please feel free to ask me and I will gladly help you out!!
~Zoey