Question

Josie has $80. Addie has $60.

Answer 1

Month      1   |    2        3        4
            _|___|____|_____|______                            |      
           J |  80 |   120|  150|   180
              |       |         |          |   
           A | 60  |   100|    140|   180

So four months until they have the same amount of money.

Answer 2

Oh wow that was easy lol  in 2 months both of them will have $140