In a 100 metres race. A runs at a speed of 2 metres per seconds. If A gives B a start of 4 metres and still beats him by 10 seconds, find the speed of B.
1.6 m/sec.
4 m/sec.
2.6 m/sec.
1 m/sec.
Explanation:
Speed of A = 2 m/s
$\text{Time taken by A to run 100 m }\dfrac{\text{distance}}{\text{speed}}=\dfrac{100}{2}\text{ = 50 seconds}$
A gives B a start of 4 metres and still A beats him by 10 seconds
=> B runs $\left(100-4\right)$=96 m in $\left(50+10\right)$=60 seconds
$\text{Speed of B = }\dfrac{\text{distance}}{\text{time}}=\dfrac{96}{60}\text{ = 1.6 m/s}$