You incorrectly chose to subtract the two numbers. They should have been added. There are two correct methods for adding mixed units problem.
Method 1
5 feet 7 inches converts as:
5 feet x 12 inches/foot = 60 inches.
60 inches + 7 inches = 67 inches.
2 feet 6 inches converts as:
2 feet x 12 inches/foot = 24 inches.
24 inches + 6 inches = 30 inches.
Then
67 inches + 30 inches = 97 inches.
Convert this back to mixed units.
97 inches divided by 12 inches/foot = 8 feet 1 inch.
Method 2
Start with the inches.
7 inches + 6 inches = 13 inches.
But 13 inches is more than 1 foot.
13 inches divided by 12 inches/foot = 1 foot 1 inch.
Now add the feet.
5 feet + 2 feet + 1 foot (from the inches column) = 8 feet.
Therefore the answer is 8 feet 1 inch.
If George placed a 3 feet 9 inches tall model airplane atop a 1 foot 4 inches tall display base, how tall would the airplane and base be together?
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