Frank has $7 in one dollar bills because 7 x 1 = <<7*1=7>>7
Frank has $20 in five dollar bills because 4 x 5 = <<20=20>>20
Frank has $20 in ten dollar bills because 2 x 10 = <<2*10=20>>20
Frank has 67 dollars in total because 7 + 20 + 20 + 20 = <<7+20+20+20=67>>67
Frank spent $63 because 67 - 4 = <<67-4=63>>63
Frank bought 21 pounds of peanuts because 63 / 3 = <<63/3=21>>21
He eats 3 pounds a day on average because 21 / 7 = <<21/7=3>>3
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