# Aptitude Question ID : 94354

If a : b = c : d, then $\frac{ma+nc}{mb+nd}$ is not equal to :
[A]$\frac{a}{b}$
[B]$\frac{c}{d}$
[C]$\frac{c-a}{b-d}$
[D]$\frac{a+c}{b+d}$

$\mathbf{\frac{a+c}{b+d}}$
$a : b = c : d$
$=> \frac{a}{b} = \frac{c}{d} = \frac{ma}{mb} = \frac{nc}{nd}$
$=> \frac{a+c}{b+d} = \frac{ma+nc}{mb+nd}$
Hence option [D] is correct answer.