During a game, Eng Soon, Fauzi and Harish scored an average of 68.5 points. Gary joined the game and the average score of the four children became 70.

1. Calculate the total score of the first three children

Total score of 3 children = $68.5 \times 3 = 205.5$

2. Calculate the total score of all four children

Total score of 4 children = $70 \times 4 = 280$

3. Find Gary's score by subtracting the total of the first three from the total of all four

Gary's score = $280 - 205.5 = 74.5$

1. Find the total score of the four children

Total score $= 4 \times 70 = 280$

2. Find Gary's score (from part a)

Total score of 3 children $= 3 \times 68.5 = 205.5$
Gary's score $= 280 - 205.5 = 74.5$

3. Calculate the percentage of the total score that Gary scored

Percentage $= \frac{74.5}{280} \times 100\% \approx 26.607\%$

4. Round the percentage to the nearest whole number

$26.607\% \approx 27\%$