Problem: in what time will a train 100 metres long cross an electic pole , if its speed be 144 km / hr ?
Rationale: "sol . speed = [ 144 x 5 / 18 ] m / sec = 40 m / sec . time taken = ( 100 / 40 ) sec = 2.5 sec . answer a"
annotated_formula: divide(100, multiply(144, const_0_2778))