Question 1187378
C=$2.57+$0.54+$0.52 (x-1), where x is the number of total minutes used.
5.19=2.57+0.54+0.52(x-1)
2.62=0.54+0.52(x-1)
2.08=0.52(x-1) divide both sides by 0.52
4=x-1
x= 5 minutes 
$2.57
$0.54
$2.08 for 4 more minutes
sum is $5.19