45 3/6+54 4/6

To add 45 3/6 and 54 4/6, first we need to add the whole numbers together and then add the fractions together.

Whole numbers: 45 + 54 = 99

Fractions: 3/6 + 4/6 = 7/6

So, the sum of 45 3/6 and 54 4/6 is 99 7/6.