Question

suma valorilor numerelor naturale xy scrise in baza 10 astfel incat xy5xy supra xy+5 iar xy apartine N este: a 140 b 120 c 100 d 125


URGENNTTTT

Answer 1

Răspuns:

Explicație pas cu pas:

xy+5 l xy5xy

xy5xy= 1.000 xy +500+xy= 1.001 xy +500

-

xy+5 l 1.001 xy+500

xy+5 l xy +5

xy+5 l 1.001 *( xy+5)

xy+5 l 1001xy+ 5.005

xy+5 l ( 1.001 xy +5.005 ) - ( 1.001 xy +500)

xy+5 l 1001 xy +5.005 - 1.001 xy -500

xy+5 l 5.005-500

xy+5 l 4.505

xy+5 ∈ D₄₅₀₅= { 1,5,17 ,53, 85 ,265 , 901 , 4.505 } :5

xy∈{12 , 48 ,80 }

12+48+80 = 140 (a)