Question

Gretchen is using an overhead projector to enlarge a drawing so she can make a poster. The original drawing measures 60 mm wide by 80 mm high. She moves the projector so that the width of the projected image is 300 mm. If the original drawing and the projected image are similar figures, what will be the height of the projected image?

A. 440 mm

B. 225 mm

C. 180 mm

D. 400 mm

Answer 1

Get a scale factor using the two known widths. Then use that scale factor to determine the projected length.
(projected image)/(original image) = (300 mm)/(60 mm) = 5
The scale factor is 5, which means the projected image is 5 times larger than the original. Since the original height is 80 mm, multiply 80 mm by 5 to get the projected height.

Answer 2

Gretchen is using an overhead projector to enlarge a drawing so she can make a poster. The original drawing measures 60 mm wide by 80 mm high. She moves the projector so that the width of the projected image is 300 mm. If the original drawing and the projected image are similar figures, what will be the height of the projected image