A model plane is 1/48 the size of the actual plane. If the model plane is 28 inches long, how long is the actual plane?

1 Answer
May 30, 2017

Answer:

#112 feet#

Explanation:

The particular wording of the question is stating that the model is the fraction #1/48"th"# of the whole plane. In other words, this is a fraction. Not a ratio. The two are quite different.

Let the actual length of the plane be #x# in inches.

Then we have:

#1/48xx x=28#

Multiply both sides by #color(red)(48)# - gets the #x# on its own.

#color(green)(1/48 xx xcolor(red)(xx48)" "=" "28color(red)(xx48))#

#color(green)((color(red)(48))/48 xx x" "=" "28color(red)(xx48))#

But #48/48=1 and 1xx x=x#

#x=1344" inches"#

To change this into feet we need to determine how many lots of 12 inches we can fit into 1344 inches (12 inches = 1 foot).

#1344/12=112 feet#