1/3 part of a certain journey is covered with the speed of 25 km/hr, 1/2 part of the journey is covered with the speed of 45 km/hr and the remaining part covered with the speed of 37.5 km/hr. What is the average speed (in km/hr) for the whole journey?
In a certain code language, 'x' represents '+', '÷' represents 'x', '' represents '÷' and '+' represents ''. Find out the answer to the following question.