Exact tape-measure math
Add feet, inches, and fractions without converting to decimals.
Keep the measurements in the same form you read from a tape measure. This worked example stays exact from input to answer.
The example
5′ 3-7/8″ + 2′ 11-1/4″ = 8′ 3-1/8″
Why the answer is exact
First convert the feet to inches while keeping the fractions:
5′ 3-7/8″ = 63-7/8″ = 511/8″2′ 11-1/4″ = 35-1/4″ = 282/8″
Now add the numerators:
511/8″ + 282/8″ = 793/8″ = 99-1/8″
Ninety-six inches is eight feet, leaving 3-1/8 inches:
99-1/8″ = 8′ 3-1/8″
Enter it in ShopMath
- Use the feet, inches, and fraction keys to enter 5′ 3-7/8″.
- Choose addition.
- Enter 2′ 11-1/4″.
- Choose equals and confirm 8′ 3-1/8″.
ShopMath for iPhone
Available on the App Store.
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