Question

The actual length (L) of a rectangle is 27 centimeters. Use the scale drawing of the rectangle to find the actual width (W).

Answer 1

The ratio of the length to the width is $\rm \dfrac{L}{W}$.
The ratio of the sides will be the same for the scale and actual figures.

$\rm \dfrac{2.4}{3.6}=\dfrac{27}{W}$

I took the L/W of the scale figure
and set it equal to the L/W of the actual figure.

Now we can solve for the unknown width.
Cross-multiplication gives us this,

$\rm 2.4W=3.6\cdot27$

Divide by 2.4 and simplify,

$\rm W=40.5$

Hope that helps! :)

Answer 2

Answer:

18 centimeters.

Step-by-step explanation:

To solve this question, we just have to use proportions. The given rectangle is showing a ratio that helps a lot to find the answer. In other words, we can use the rule of three to solve this problem.

$\frac{width}{length}=\frac{2.4}{3.6}=\frac{x}{27}$

Now, we solve for $x$:

$\frac{2.4}{3.6}=\frac{x}{27}\\x=\frac{2.4(27)}{3.6}=18$

Therefore, according to the proportion, the actual width is 18 centimeters.

When we use proportions and ratios like this problem, we have to make sure that we are placing magnitudes in the right order, that is, if we place width in the numerator, it always has to be in that position, placing the width in the denominator in the other ratio would be completely wrong.