Sorry

This answer is incorrect.

You correctly chose to add the two numbers; however, you forgot to carry into the feet column.

There are two correct methods for adding mixed units problems.

Method 1

Example

Say you had to add 5 feet 7 inches to 2 feet 6 inches.

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

Example

Say you had to add 5 feet 7 inches to 2 feet 6 inches.

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.

Another Try

If you feel that you understand the above example, let's try another problem.

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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