johnny travels a total of one hour to and from school . on the way there he jogs at 5 miles per hour and on the return trip he gets picked up by the bus and returns home at 30 miles per hour . how far is it to the school ?
"answer : e ) 6.9 miles . average speed for round trip = 2 * a * b / ( a + b ) , where a , b are speeds so , average speed was = 2 * 5 * 30 / ( 5 + 30 ) = 6.9 m / hr the distance between schoolhome should be half of that . ie . 6.9 miles answer e"
multiply(divide(const_1, add(divide(const_1, 5), divide(const_1, 30))), const_1_6)