A →_______60Km_________← B
Let the speed of A = x kmph and that of B = y kmph
According to the question;
x × 6 + y × 6 = 60
Or, x + y = 10 ——— (i)
And,
$\begin{array}{l}
\left(\frac{2 x}{3} \times 5\right)+(2 y \times 5)=60 \\
\text { Or, } 10 x+30 y=180 \\
\text { Or, } x+3 y=18-\ldots \ldots \text { (ii) } \\
\text { From equation (i) } \times 3-\text { (ii) } \\
3 x+3 y-x-3 y=30-18 \\
\text { Or, } 2 x=12 \\
\text { Hence, } x=6 \text { kmph }
\end{array}$
Alternate:
Speed Time and Distance mcq solution image
∵ They meet after 6 hours if they walk towards each other i.e., their speed will be added.
So, their relative speed in opposite direction
$=\frac{\text{ Distance }}{\text{ Time }}=6$
Relative speed in opposite direction :
$(\rightleftharpoons)=10 \mathrm{~km} / \mathrm{h} \ldots \ldots$
According to the question,
$\begin{array}{l}\Rightarrow\frac{2}{3}A+2B=\frac{60}{5}\\
\Rightarrow\frac{2}{3}A+2B=12\\
\Rightarrow A+3B=18\\
\Rightarrow B^{\prime}s\text{ Speed }=\frac{18-}{3}\\
\Rightarrow A+B=10\\
\Rightarrow A+\frac{18-A}{3}=10\\
\Rightarrow3A+18-A=30\\
\Rightarrow2A=12\\
\Rightarrow A^{\prime}\text{ s speed }=6\mathrm{~km}/\mathrm{h}\end{array}$