# Proportions

• Jul 25th 2006, 08:34 PM
rlp
Proportions
Problem: The instructor of an introductory computer course wants to make a wall chart of a computer desktop for her students. To make it as realistic as possible, she would like the desktop icons to be proportional to the size of her 6'x6' chart. If the icons on her 15"x15" PC screen are 3/8"x3/8", how large should they be on her wall chart?
• Jul 25th 2006, 10:31 PM
CaptainBlack
Quote:

Originally Posted by rlp
Problem: The instructor of an introductory computer course wants to make a wall chart of a computer desktop for her students. To make it as realistic as possible, she would like the desktop icons to be proportional to the size of her 6'x6' chart. If the icons on her 15"x15" PC screen are 3/8"x3/8", how large should they be on her wall chart?

The 15" side of a screen corresponds to a 6' side of the chart (that is 72").

Therefore everything on the chart is 72/15 times larger than it is on the screen.

The icons are 3/8" on the screen so they are (72/15)x(3/8)" on the chart.

RonL
• Jul 25th 2006, 10:37 PM
Soroban
Hello, rlp!

Quote:

The instructor of a computer course wants to make a wall chart of a computer desktop for her students.
To make it as realistic as possible, she would like the desktop icons to be proportional to the size of her 6'x6' chart.
If the icons on her 15"x15" PC screen are 3/8"x3/8", how large should they be on her wall chart?

The enlargement is from a 15-inch square screen to a 72-inch square wall chart.

The chart is $\displaystyle \frac{72}{15} \,= \,4.8$ times as large at the screen.

Hence, the icons will be: $\displaystyle \frac{3}{8} \times 4.8 \,= \,1.8$-inch squares.