The total ratio representing the yellow scores that Taylor got is 7+6=<<7+6=13>>13
The difference in the ratio between the number of black and white scores Taylor used is 7-6=<<7-6=1>>1
The fraction representing the difference in the ratio between the number of black and white scores Taylor used is 1/13, representing 1/13*78=6
2/3 of the difference between the number of black and white scores Taylor used is 2/3*6=<<2/3*6=4>>4
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