the distance between two cities a and b is 870 km . a train starts from a at 8 a . m . and travel towards b at 60 km / hr . another train starts from b at 9 a . m and travels towards a at 75 km / hr . at what time do they meet ?
"explanation : suppose they meet x hrs after 8 a . m then , [ distance moved by first in x hrs ] + [ distance moved by second in ( x - 1 ) hrs ] = 870 . therefore , 60 x + 75 ( x - 1 ) = 870 . = > x = 7 . so , they meet at ( 8 + 7 ) i . e , 15 = > 3 pm answer : c )"
add(divide(add(870, 75), add(60, 75)), 8)