Question 1148636
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The additional cost of the additional 34 minutes is $4.08; the cost per minute is $4.08/34 = $0.12.<br>
81 minutes is an additional 16 minutes past 65 minutes; the cost of the additional 16 minutes is 16*$0.12 = $1.92.<br>
The credit remaining after 81 minutes is $12.20 - $1.92 = $10.28.<br>