Subtract 41 1/2 minutes from 60 minutes, and then divide the result by 1/2 minute.
60 => 59 2/2
- 41 1/2 => -41 12
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18 1/2 minutes worth of commercials.
Divide 18 1/2 by 1/2;
37
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2
37 2
-------- = ------ * ----- = 37 There were 37-1/2-minute commercials. ;(
1 2 1
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2