The cost of a long distant telephone call is $0.36 for first minutes and $0.21 each additional minutes or portion thereof. Write an inequality representing the number of minutes a person could talk with out exceeding $3.00

would this be written as
0.36+0.21(x-1)<$3.00

0.36+(0.21(x)+0.21(-1))<3.00
0.36+(0.21x-0.21)<3.00
0.21x+0.15<3.00
0.21x<-0.15+3.00
0.21x<2.85
0.21x/0.21<2.85/0.21
x<2.85/0.21
x<2.85/0.21
x<13.57

to check i did this
0.36+0.21(13.57-1)<3.00
0.36+0.21(12.57)<3.00
0.36+2.639<3.00
0.36+2.64<3.00
3.00=3.00

aim i correct on this if i am not please tell me where i need look at to fix this

Your math is correct but the answer has to be 13 minutes, since the extra 0.57 minutes, or even 0.01 minute, would be billed as a full minute, making the bill 3.01