A train crosses a 120-metre and a 70-metre long plat form in 17 seconds and 12 seconds respectively. What is the speed of the train ?  Select the correct option:
A) 10 ms-1	B) 16 ms-1	C) 20 ms-1	D) 24 ms-1	E) 45 ms-1
Explanation :   let the length of the train be x   ∴ 120+x/17 = 70+x/12   1440 + 12x = 1190 + 17x   ∴ x = 250/5= 
<gadget id="calculator">250/5</gadget>
<output>50</output>
50m   ∴ Speed= 120+50/17 = 170/17= 
<gadget id="calculator">170/17</gadget>
<output>10</output>
10 ms-1   10 ms-1nswer : Option 10 ms-1
<result>A</result>
A train crosses a 120-metre and a 70-metre long plat form in 17 seconds and 12 seconds respectively. What is the speed of the train ?