eterminati numerele naturale care au urmatoarele descompuneri in baza 10: a) 4×10^3+7×10^2+8 ,
b) 6×10^4+4×10^3+7×10^2+9×10 ;
c) 8×10^3+9×10+5 ;
d) 7×10^5+4×10^3+8×10^2+3 ;
e) 4×10^3+9×10^2+6 ;
f) 5×10^2+9×10+8 .

Răspuns:

a)

4 × 10^3 + 7 × 10^2 + 8 =

4 x 1000 + 7 x 100 + 8 =

4000 + 700 + 8 =

4708

b)

6 × 10^4 + 4 × 10^3 + 7 × 10^2 + 9 × 10 =

6 x 10000 + 4 x 1000 + 7 x 100 + 9 x 10 =

60000 + 4000 + 700 + 90 =

64790  

c)

8 × 10^3 + 9 × 10 + 5 =

8 x 1000 + 9 x 10 + 5 =

8000 + 90 + 5 =

8095  

d)

7 × 10^5 + 4 × 10^3 + 8 × 10^2 + 3 =

7 x 100000 + 4 x 1000 + 8 x 100 + 3 =

700000 + 4000  + 800 + 3 =

704803

e)

4 × 10^3 + 9 × 10^2 + 6 =

4 x 1000 + 9 x 100 + 6 =

4000 + 900 + 6 =

4906

f)

5 × 10^2 + 9 × 10 + 8 =

5 x 100 + 90 + 8 =

500 + 90 + 8 =

598