# Which is better investment: 11% stock at 143  or  93/4% stock at 117?

Option :

Explanation:

Solution:
$\begin{array}{rl}& \text{Let}\phantom{\rule{thinmathspace}{0ex}}\text{investment}\phantom{\rule{thinmathspace}{0ex}}\text{in}\phantom{\rule{thinmathspace}{0ex}}\text{each}\phantom{\rule{thinmathspace}{0ex}}\text{case}\phantom{\rule{thinmathspace}{0ex}}\text{be}\\ & Rs.\phantom{\rule{thinmathspace}{0ex}}\left(143×117\right).\\ & \text{Income}\phantom{\rule{thinmathspace}{0ex}}\text{in}\phantom{\rule{thinmathspace}{0ex}}{\text{1}}^{\text{st}}\phantom{\rule{thinmathspace}{0ex}}\text{case}\\ & =Rs.\left(\frac{11}{143}×143×117\right)\\ & =Rs.\phantom{\rule{thinmathspace}{0ex}}1287.\\ & \text{Income}\phantom{\rule{thinmathspace}{0ex}}\text{in}\phantom{\rule{thinmathspace}{0ex}}{\text{2}}^{\text{nd}}\phantom{\rule{thinmathspace}{0ex}}\text{case}\\ & =Rs.\phantom{\rule{thinmathspace}{0ex}}\left(\frac{39}{4×117}×143×117\right)\\ & =Rs.\phantom{\rule{thinmathspace}{0ex}}1394.25\\ & \text{Clearly,}\phantom{\rule{thinmathspace}{0ex}}9\frac{3}{4}\mathrm{%}\phantom{\rule{thinmathspace}{0ex}}\text{stock}\phantom{\rule{thinmathspace}{0ex}}\text{at}\phantom{\rule{thinmathspace}{0ex}}117\phantom{\rule{thinmathspace}{0ex}}\text{is}\phantom{\rule{thinmathspace}{0ex}}\text{better}.\end{array}$

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