Question

dau coroana va rog foarte mult ​

Answer 1

Răspuns:

a:12=r

a=12r+r

a=13r

r=1=>a=13*1=13

r=2=>a=13*2=26

r=3=>a=39

r=4=>a=52

r=5=>a=65

r=6=>a=78

r=7=>a=91

13+26+39+52+65+78+91 = 364 rotunjit =400