Question

A drawing of a property is to the scale of 0.5 inches to 6 feet. If a wall is 30 feet long what would its length be on the drawing?

Answer 1

`2.5` inches

Explanation:

Since `6` feet correspond to `0.5` inches
`1` foot will correspond to `0.5/6` inches
`30` feet will correspond to `(0.5/6)30` inches = `2.5` inches

Answer 2

The wall will be `2 1/2` inches long on the drawing

Explanation:

Using ratio:

Write 0.5 inches to 6 feet as:

`" "0.5/6`

Let the unknown scale down size be `x`

Then we have:

`" "color(brown)(0.5/6=x/30)`

To get `x` on its own multiply both sides by 30

`color(brown)(0.5/6=x/30)" "->" "color(brown)(color(blue)(30xx)0.5/6" "=" "(color(blue)(30))/30 xx x)`

But `30/30=1`

`" "(30xx0.5)/6=1xx x`

`" "x=2 1/2`