Question

In covering a distance of $30km$. Amit takes $2hrs.$ more than suresh. If Amit doubles his speed, he would take one hour less than suresh. Amit's speed is

• A. $5km/hr$
• B. $7.5km/hr$
• C. $6km/hr$
• D. $6.25km/hr$

Answer 1

The correct option is A $5km/hr$

Let speed of Amit be $xkm/hr$ and speed of Suresh by $y$ $km/hr$
ATP
$\frac{30}{x}-\frac{30}{y}=2$
$\frac{1}{x}-\frac{1}{y}=\frac{1}{15}........\left(i\right)$
and $\frac{30}{y}-\frac{30}{2x}=1$
$-\frac{1}{2x}+\frac{1}{y}=\frac{1}{30}......\left(ii\right)$
$\frac{1}{x}-\frac{1}{y}=\frac{1}{15}$
$-\frac{1}{2x}+\frac{1}{y}=\frac{1}{30}$
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$\frac{1}{2x}=\frac{1}{10}$
$x=5$
So, Amit's speed $=5km/hr$