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Ratios and Proportions
A proportion is a name we give to a statement that two ratios are equal. It can be written in two ways:
two equal fractions, a = c
b d
or,
using a colon, a:b = c:d
(note found from www.math.com)
To find the proportion you must cross multiply.
Step 1 X = 1 ß multiply 1 by 15 =15
15 5 ß multiply 5 by X =5x
=5x = 15
Step 2 Divide everything by 5.
*All ways divide the numbers by the number front of the variables*
5x = 15
5 5
X=3