Question 82810
[c/d + 3] / [4 + c/d]
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Simplify numerator and denominator separately:


[(c+3d)/d] / [(4d+c)/d]

Invert the denominator and multiply to get:

[(c+3d)/d] * [d/(4d+c)]
 
Now the d in numeratof and denominator cancel leaving you with:

[(c+3d)] * [1/(4d+c)]

(c+3d)/(4d+c)

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Cheers,
Stan H.