private float calculateChallengePaceFromProgress(int progress){
  return CHALLENGE_PACE_MIN_MINUTES_PER_MILE + ((1.0f - ((float)progress) / CHALLENGE_PACE_SEEK_BAR_MAX) * CHALLENGE_PACE_RANGE_MINUTES_PER_MILE);
}

private float calculateChallengePaceFromProgress ( int progress ) { return CHALLENGE_PACE_MIN_MINUTES_PER_MILE + ( ( 1.0f - ( ( float ) progress ) / CHALLENGE_PACE_SEEK_BAR_MAX ) * CHALLENGE_PACE_RANGE_MINUTES_PER_MILE ) ; }
calculates challenge pace based on seekbar progress .
