Question

On a scale drawing, 1 millimeter equals 4 centimeters. If a line on the drawing is 45 millimeters, how many meters is it actually?

18 m
180 m
1,800 m
1.8 m

Answer 1

Answer:

D. 1.8 m

Step-by-step explanation:

On a scale drawing,

1 millimeter = 4 centimeters.

A line on the drawing is 45 millimeters, then

1 mm - 4 cm

45 mm - x cm

Write a proportion:

$\dfrac{1}{45}=\dfrac{4}{x}$

Cross multiply:

$x=45\cdot 4\\ \\x=180\ cm$

Note that

$1\ m=100\ cm,$

then

1 m - 100 cm

y m - 180 cm

Write a proportion:

$\dfrac{1}{y}=\dfrac{100}{180}$

Cross multiply:

$100y=180\\ \\y=1.8\ m$