To make an international call, there is a flat fee of $3.15 plus $0.05 for every minute that you talk. If you were charged $5.10 for making an international call, for how many minutes did you talk?

39 minutes

Step-by-step explanation:

a = 0.05m + 3.15 where a=the total charged, m=the amount of minutes

5.10 = 0.05m + 3.15

1.95 = 0.05m

1.95/0.05 = m

m = 39 minutes

1/3 + 1/3 ≠ 2/6 because 1/3 alone = 2/6  

step by step explanation:

1/3 + 1/3 = 2/3       2/3=4/6