Question

An industrial model builder need several pieces of wire that are 7 3/8 inches long. How many whole pieces of wire of this length can be cut from a spool containing 100 inches of wire? How much wire is left over

Answer 1

Answer: 13 whole pieces of wire can be cut from that spool and
`4.125\ inches` of wire is left over.

Explanation:

Convert from mixed number to improper fraction. To do it you must multiply the whole numbe part by the denominator of the fraction and then add the product to the numerator. The denominator does not change. Then:

`7(3)/(8)in=((7*8)+3)/(8)in=(59)/(8)in`

Since the spool contains 100 inches of wire, you must divide this lenght by
`(59)/(8)in`:

`(100in)/((59)/(8)in)=(800)/(59)`

Convert from improper fraction to mixed number:

- When you divide the numerator 800 by the denominator 59, the quotient is 13 (this is the whole number part)

- The remainder is 33 (This is the numerator of the fraction).

- The denominator does not change.

Then:

`13(33)/(59)`

Therefore 13 whole pieces can be cut from that spool.

The amount of wire left over is:

`100in-((59)/(8)in)(13)=4.125in`