two trains 110 meters and 180 meters in length respectively are running in opposite directions , one at the rate of 80 km and the other at the rate of 65 kmph . in what time will they be completely clear of each other from the moment they meet ?
"t = ( 110 + 180 ) / ( 80 + 65 ) * 18 / 5 t = 7.20 answer : a"
divide(add(110, 180), multiply(add(80, 65), const_0_2778))