At the beginning of the game it is assumed the bowler has knocked more pins down than left standing. Pressing on the pins the bowler left has proven to be a quicker way to score rather than pressing on every pin the bowler knocked down. After the first ball is rolled and pins are left standing, pressing one the pins the bowler knocked down will complete the frame. If all pins were knocked down on the second roll, the frame would be marked as a spare. If the bowler rolled a strike, simply pressing on one of the next frames will move to the next frame.
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