0 votes 0 votes Two persons start walking on a road that diverge at an angle of $120^{\circ}$. If they walk at the rate of $3$km/h and $2$km/h respectively. Find the distance between them after $4$hrs. $4\sqrt{19}$ km $5$ km $7$ km $8\sqrt{19}$ km Quantitative Aptitude nielit2019feb-scientistc quantitative-aptitude speed-distance-time + – Lakshman Bhaiya asked Apr 1, 2020 • edited Nov 21, 2022 by gatecse Lakshman Bhaiya 13.8k points 857 views answer comment Share See all 0 reply Please log in or register to add a comment.
0 votes 0 votes Ans is option (A) Using the cosine rule of triangle trigonometry , $cosC=\frac{a^{2}+b^{2}-c^{2}}{2ab}$ $\Rightarrow$ $cos120^{\circ}=\frac{64+144-c^{2}}{2\times8\times12}$ $\Rightarrow$ $c^{2}=304$ $\Rightarrow$ $c=4\sqrt{19}km$ haralk10 answered Apr 13, 2021 haralk10 778 points comment Share See all 0 reply Please log in or register to add a comment.