Respuesta :

3/10 can stay the same,

2/5 >>

2*2 = 4
5*2 = 10

4/10 and 3/10 
okay so if 3/10 and 2/5 are uncommon than you have to find a number that there both divisible by in this case its 2 so 2 x 2  4
                                                                  ----     ------
                                                                    5  x 2 10