I glossed over 9 x 19 = 101 a couple chapters back because maybe they made a typo with 0 instead of 8, but this one was just so simple. It also looks like they missed a line to make it correct. There had to be a third person since she there was the 2x part and the answer is 34 but she comes out with 17, which is half that. So maybe an older sibling or uncle or something was twice his age, then mom is 3 years older and dad 5 years older than that.