Carlotta can drive from her home to her office by one of two possible routes. If she must also return by one of these routes, what is the distance of the shorter route?

(1)When she drives from her home to her office by the shorter route and returns by the longer route, she drives a total of 42 kilometers.

(2)When she drives both ways, from her home to her office and back, by the longer route, she drives a total of 46 kilometers.