hi. i don't know if I get the question, but: 19 x 5 x 20 -12 =1888 and 26.04.02 has 26:02=13, ((if you want, division could be the fourth symble normally written so, +, -, *, : )).

So: (19 x 5 x 20 -12)-(26:02)=1875 . if you want the 6 of august: you could take 26.04.02, extract the 6 and add all the other numbers, i.e. 2+0+4+0+2=8. so you have 6.8 which is the 6th of august. at least in europe, or if you want you have 8.6.

hope this helps..