Respuesta :

For 20 and 26, it would be 26. 
26*2 = 52
26*3 = 78
26*4 = 104
26*5 = 130
26*6 = 156 
26*7 = 182
26*8 = 208
26*9 = 234
26*10 = 260
Only 260 is where 20 is able to be a multiple.