Randy has 20 – 12 = <<20-12=8>>8 years until he is 20.
He must practice 10,000 hours / 8 years = <<10000/8=1250>>1,250 hours a year to become an expert.
There are 52 weeks in a year – 2 weeks of vacation Randy plans to take = <<52-2=50>>50 weeks of practice for Randy.
Randy will practice Monday – Friday, which is 5 days a week, so 50 weeks x 5 days = <<50*5=250>>250 days of practice each year.
Randy will need to practice 1250 hours / 250 days = <<1250/250=5>>5 hours each day.
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