Question

george is making 8 gallons of tropical trip punch. he has already poured in $1\frac{3}{4}$ gal of pineapple juice and $2\frac{1}{2}$ gal of orange juice. the only other ingredient is 7 - up. how much 7 - up does george need? \underline{\quad\quad} gal

Explanation:

Step1: Convert mixed numbers to fractions

$1\frac{3}{4} = \frac{7}{4}$, $2\frac{1}{2} = \frac{5}{2}$, $8 = \frac{32}{4}$

Step2: Add the juices together

$\frac{7}{4} + \frac{5}{2} = \frac{7}{4} + \frac{10}{4} = \frac{17}{4}$

Step3: Subtract sum from total punch

$\frac{32}{4} - \frac{17}{4} = \frac{15}{4}$

Step4: Convert back to mixed number

$\frac{15}{4} = 3\frac{3}{4}$

Answer:

$3\frac{3}{4}$ gal