Question 457198
35 + .05x < 55 + .02x
---
Yes, you need the decimals so everything
is stated in terms of dollars.
---
But you need to reverse the inequality
because you want the 2nd plan to be 
less expensive:
----------
Solve: 35 + .05x > 55 + .02x
---
0.03x > 20
x > 20/0.03
x > 666.67
---
2nd plan is less expensive if 667 phone calls are made.
========================================================
Cheers,
Stan H.
===========