???????????? yu meen the leng av the traen= 120 meters ?????????
???????? & platform=130 meters long ????????????
Then wot?????????
Maebee yu assume front av traen be at 1 end av platform ??????????
& maebee yu want time for END av traen tu get tu other end av platform ??????????????
That meen traen gotta muev 120 meters (NOT 130 & not 120+130)
speed=50 km/our=50,000/our=13.888888888888 meter/sekond
time=120/13.88888888888...
8.64 sekonds
BUT...yu did NOT giv traen time tu get up tu speed