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Proportion
Meaning of proportion
Proportion is an equality of two or more ratios
Or proportion is two or more ratios have the same value
To solve for an unknown in a proportion, you can use cross-multiplication:
a×d=b×c
(1 = 2) , ( 80 ???? = 160 ???? )
10 20 1 h?? 2 h??
Remark(1):
? In the following proportion ( ?? = ?? )
? a is called 1st proportional ?? ??
? c is called 3rd proportional
b is called 2nd proportional
d is called 4th proportional
?The product of means = the product of extremes.
i.e. (a x d = b x c).
( 1 = 2) ,then 1× 20 = 2 × 10
10 20
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