r>Blowers sets off the first detonation, lights the first flare at both ends and another flare at one end… all simultaneously (go with me on this.) The first flare burns out in exactly 30 minutes. Blowers then knows that the second flare has exactly 30 minutes to go before it also burns out completely. But he doesn’t wait for that.
He lights the other end of the second flare. It means that the second flare will be burnt out completely after 15 minutes, which of course adds up to 45minutes!
Boom!
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