neuro cell phone plan is $40 per month plus a $0.15 per per charge for each minute of 200 minutes or call time if he if his cell phone bill was $58 how many minutes out of 200 minutes phone plan did he spend talking on his cell phone
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So, when doing this, you will first subtract your $40, leaving you with $18. Now take $18 and divide it by $0.15, giving you 120. He spent 120 minutes.