Answer: 11/18
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Explanation:
We need to add the fractions, but first we need to get each fraction to have the LCD (lowest common denominator) of 18
18 is the LCM of the denominators 6 and 9
The fraction 1/6 turns into 3/18 when multiplying top and bottom by 3
The fraction 4/9 turns into 8/18 after multiplying top and bottom by 2
Therefore,
(1/6) + (4/9) = (3/18) + (8/18) = (3+8)/18 = 11/18
So Mike has a total of 11/18 of a gallon of paint when combining the two given amounts 1/6 a gallon of blue paint and 4/9 of a gallon of green paint.