First find the total number of hours Brendan works for the 8-hour shifts: 2 shifts * 8 hours/shift = <<2*8=16>>16 hours
Then find the total number of hours Brendan works by adding those hours to the 12-hour shift: 16 hours + 12 hours = <<16+12=28>>28 hours
Now find Brendan's total wage earnings by multiplying his $6/hour wage by the number of hours he works: $6/hour * 28 hours = $<<6*28=168>>168/week
Now figure out how much Brendan makes in tips by multiplying the number of hours he works by the amount of tips he makes per hour: $12/hour * 28 hours/week = $<<12*28=336>>336/week
Now divide that number by 3, since Brendan only reports a third of his tips: $336/week / 3 = $<<336/3=112>>112/week
Now add Brendan's wage earnings to that number to find how much income he reports to the IRS each week: $168/week + $112/week = $<<168+112=280>>280/week
Finally, multiply Brendan's reported income by his tax rate to find how much he pays in taxes each week: $280/week * .2 = $<<280*.2=56>>56/week
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