1) If you don't want to get too deeply involved with fractions, assume that there are 100 games.
If they have finished 75% of the season, they will have played 75 games.
If they have won 40% of the games they have played, they will have won 40% of 75 games, which are 30 games.
This also means that they have lost 75 - 30 = 45 games.
Their record is now: 30 W and 45 L
To have a final winning percentage, they will need to end with 50 W and 50L.
So, they will need to win 20 games and lose only 5 games.
To win 20 out of the remaining 25 games, their winning percentage will have to be: 20 / 25 = 80% of the remaining games.
This analysis will work no matter how many games were actually played.
2) Since Jim brought 2 gallons and Kim brought 1.75 gallons, together they brought 3.75 gallons.
To divide this evenly: 3.75 divided by 3 means that each person would have 1.25 gallons.
So, Jim will have to give Lenny 0.75 gallons and Kim will have to give Lenny 0.50 gallons.
Of the total amount (0.75 + 0.50 = 1.25 gallons), Jim will give up 0.75 gallons: 0.75 / 1.25 = 0.60 (or 60%).
Kim will give up 0.50 gallons: 0.50 / 1.25 = 0.40 (or 40%).
Therefore, Jim should get 60% of $2.00, or $1.20
and Kim should get 40% of $2.00, or $0.80.