The true finishing time is 22.2 seconds. The prediction furthest from this is 22.9 seconds. This is a difference of 22.9-22.2 = 0.7 seconds. Divide this over the true time value to get (0.7)/(22.2) = 0.03153 which is approximate.
Move the decimal point to the right 2 spots to get to 3.153%; round this value however you need to.
