Race 1 (100m all)
Tom covers 100m to Henry's 95m.
Tom 1 : .95 Henry
Race 2 (105m for Tom, 100m for Henry)
Tom does 1 * 105 m = 105 m (100m course + 5m delay)
In the time that Tom covers his 105m, Henry only covers 105m * .95 = 99.75m
So, Tom wins again, except this time by .25m instead...