Greenwood press

SIMILARITY
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equal to the ratio of the cubes of their lengths. For visualization and instructional
purposes, this would be difficult to create in a hand-held model. It unfortunately
provides misconceptions about the relative sizes and distances among planets in
our solar system.
online sources for further exploration
Map making


Nuclear medicine

Scale model of a pyramid

Scale models



Screen ratios


Understanding scale speed in model airplanes

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▼
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SLOPE
. S
EE LINEAR FUNCTIONS
;
RATES
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SQUARE ROOTS
A square root is the inverse of a squared number. The square root of 49, writ-
ten as 
√
49 or 49
1/2
, is equal to 
7, because 7
2
equals
49. Many real-world rela-
tionships involve square roots. For example, the height of liquid wax in a candle
is directly proportional to the square root of the amount of time a candle has been
burning. This information is useful in the design of candles, because the presence