Correct

This is the correct answer.

When adding mixed units, you can approach the problem in two ways.

Method 1

• Convert everything to the same units.
• Add.
• Convert back to mixed units.

Example

3 feet 6 inches converts as:

3 feet x 12 inches/foot = 36 inches.

36 inches + 6 inches = 42 inches.

1 foot 8 inches converts to:

1 foot x 12 inches/foot = 12 inches.

12 inches + 8 inches = 20 inches.

Then

42 + 20 = 62 inches.

Convert this back to mixed units.

62 divided by 12 = 5 remainder 2,

which is 5 feet 2 inches.

Method 2

• Add smallest units.
• Convert on the fly.
• Add the next smallest units.

Example

Start with the inches because they are the smallest units.

Add 6 inches and 8 inches.

6 inches + 8 inches = 14 inches.

But 14 inches is more than 1 foot.

14 divided by 12 equals 1 with remainder 2,

which is 1 foot 2 inches.

Then move to the feet column.

3 feet + 1 foot + 1 foot (the 1 foot from the inches column) = 5 feet.

Therefore, the answer is 5 feet 2 inches.

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