Slightly wrong maths on my part....

Scratch is 100 (1)

Fast(er) boat is 57 (0.57)
other boat is 85 (0.84)

So corrected time (CT) is

CT = elapsed T / (handicap/100)

100 = 100 / (100/100) (100 = 100 * 1)

Fast boat :

CT = 57 / (57 / 100)
= 100

same boat takes one minute longer

CT = 58 / (57/100)
= 101.754386

Same boat takes 56 minutes

CT = 56 / (57 /100)
= 98.24561404


Sorry !

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