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I can't figure this out. Could you be of some help?
a is proportional to b. If a = 1/4 when b = 2, find a when b = -2.5
Nate~
a is proportional to b means that you have a ratio of a1 to b1 equal to a ratio of a2 to b2 or a1/b1 = a2/b2:
Let x be the unknown amount for the 'other' a2, then(1/4)/2 = x/-2.5
multiply both sides by -2.5 getting: -2.5(1/8) = x -> -3.125 = x = a2
Note (1/4)/2 = 1/8 and 1/8 = .125 and .125(-2.5) = -3.125
Math Prof
fixed a typo
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Sherry Wallin
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