A man makes a trip in 3T hours. Two thirds of the distance travelled was by car and the remainder by boat. If his rate by car was three times his rate by boat, then the number of hours spent in the boat was:

(A) 6/5 T

(B) T

(C) 3/4 T

(D) 9/5 T

I'm confused and don't know how to start this problem. Could someone please explain to me how to get the answer?