Based on my few math knowledge, below my answers to your questions.
1 Question #1
What average odds is he/she currently betting at? Obviously he/she are playing dogs or +money. Otherwise at -110 they will only be making $570.
The average line they're playing to be up $1488 Is aprox. +106. That is 64x106=$6784(winnings) - 53x100=$5,300(lossings) total= 1484(I said aprox.)
Question #2
64/117 =.547 is 54.7% winners at whatever average odds he/she is currently betting at What would be the effective winning percentage over the same 117 plays if all his/her wagers were at the bookie's 11/10 (-110)?
Personally I won't try to mix the avg. for picking winners vs the effective winning pct. (specially in baseball) where what really matters is the units won. Let's say this is an analysis of football for example. If you want to take into account the juice on your winning/losing pct. then it will be as following:
In other words at -110 the point to break even is 52.4%. this is the number you have to beat in order to make profit (at least at flat betting), that's 2.4% advantage for the books. So another way you can get to the number you were asking is to deduct 2.4% from your winning pct.