Answer: 1/6
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Step-by-step explanation:
1.5 liters of orange juice
7.5 liters of lemonade
1.5+7.5 = 9 liters total
1.5/9 = 15/90 is the fractional amount of orange juice. Note how I multiplied top and bottom of the first fraction by 10 to get 15/90. This is the same as moving the decimal point 1 spot to the right for each value.
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From here you divide both parts by the GCF 15 to reduce
15/15 = 1
90/15 = 6
Meaning 15/90 = 1/6
So 1/6 of the drink is orange juice.