A model car was built on a scale of 1:30. If the height of the model car was 1 inches what was the height of the actual car in feet?

2 Answers
Apr 28, 2017

See the entire solution process below:

Explanation:

We can write this problem as:

#1:30 -> 1 i n:x i n#

Therefore x in = 30 in.

Because 1 ft = 12 in we can write 30 inches as:

#30 i n * (1 ft)/(12 i n) = 30 color(red)(cancel(color(black)(i n))) * (1 ft)/(12 color(red)(cancel(color(black)(i n)))) = (30 ft)/12 = 2.5 ft#

The actual height of the car was 2.5 feet.

Apr 28, 2017

#2 1/2# feet

Explanation:

Scale is ratio.

#=>"model : actual "->1:30#

Write in fraction format:

#("model")/("actual") -> 1/30#

Actually, in this case, I prefer it up the other way:

#("actual")/("model")->30/1#

But we are told that the model car is 1 inch high so we write:

#("actual")/("model")->(30" inches")/(1" inch")#

So the actual car had the height of 30 inches.

(Oh come on! That is silly! I have never seen a car 30" high!)

The question instructs that the height is to be in feet.

1 foot is the same length as 12 inches. So we need to see how many lots of 12 inches we can fit into 30 inches

Actual height in feet is #30-:12 = 2 6/12# feet #-> 2 1/2 #feet