x :205=cat si rest
x=205*c+r
r=c-1
x=205*c+c-1=206c-1
rest<205 =>
rest =0,1,2,3,...204 -deci avem 205 termeni
suma caturi=1+2+3+4+...+205=(205+1) (205-1+1):2=206*205:2=21115
⇒Suma x =206*(suma caturilor)-1*205 = 206*21115-205=4349485
2.
y:49= cat si rest
y=49*c+r
r=c+1
y=49c+c+1=50c+1
rest<49
daca cat=0,1,2,...,47
rest=1,2,3,...,48 ->avem 48 de termeni
Suma caturi= 1+2+...+47=47*48:2=1128
⇒Suma y= 50*1128+1*48 =56448
