Noelle and Micah went to the bank to open new checking accounts. The equation C=0.2n+1.20 represents the monthly cost, C, in dollars, where n is the number of checks written by Noelle. In Micah's account, the monthly cost is proportional to the number of checks written. The monthly cost for Micah's account is $1.20 for writing 3 checks. How many checks must Noelle and Micah write, if any, so that the cost of the accounts is the same for one month? What is the cost, if any?