Answer:
to get hours to minutes you multiply your hours by 3600 and to convert minutes to seconds you multiply your number by 60.
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Multiply your hours number by 60 to convert into minutes
Add the original minutes number to the product and then multiply the total minutes by 60 to get the total in seconds.
Thus 10 hours and 20 minutes
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= 10 x 60 = 600 minutes plus the original 20 minutes then = 620 minutes,
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which equals 620 x 60 = 37,200 seconds ( phew !!! )