Here's from the USBC rulebook and seems to be on point.
Commonly Asked Question – Rule 118c.
118c/1 The league rule requires three games be bowled to establish an average. A member
bowls a 120 for game one and a 150 for game two and cannot bowl game three. What
score is used for the missed game? How are average and handicap figured?
In a handicap league, if a bowler does not have an entering average or until they meet the
requirement(s) defined by league rule, handicap is based on the average of all games bowled.
In the example given, the score for game three would be calculated by adding games 1 and
2 together (120 + 150 = 270 actual pinfall), then dividing by total games bowled (270 ÷ 2 =
135 average). This will give you the bowler’s average which is used for handicapping purposes
for all games of the series. To determine the absentee score for game three, the bowler would
use the established average less ten pins (135 - 10 = 125 absentee score) unless league rules
state otherwise.
So since she bowled one full game (121), the average would be based on that. So a 121 average to base the handicap on.
So handicap 200-121=79 79X90%= a 71 handicap for each game.
and the third game would be a 121-10 for a absentee score of 111 (assuming you take 10 pins off a absentee score)
I would check with the USBC to make sure. Email them at rules@bowl.com they are pretty fast at getting back to you.
Game 1: 121 + 71 = 192 handicap game
Game 2: 105 + 71 = 176 handicap game
Game 3: 111 + 71 = 182 handicap game
Scratch series: 337
Handicap series: 337 + 213 = 550 handicap series
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