Tingting's toy is twice that of Niu Niu, so it can be understood that Niu Niu's toy is 1, Tingting's is 2, and the two add up to 72. Conversely, 72 points and 3 points, Niu Niu's, Tingting's.
72 divided by 3 of Niu Niu's.
72 divided by 3 times 2 is Tingting.