Number is right but notation looks wrong for best of three against B. There are three possible outcomes that A wins against B. 2-0, 0-1 to 1-1 to 2-1, 1-0 to 1-1 to 2-1. Probabilities are 0.36, 0.144, and 0.144. Total odds is the summation: 0.648.
Assuming A plays against C and D as well with the same odds as B, the probability A wins out right in a best out of three format would be 0.648 x 0.648 x 0.648 = 0.27