Question

Aflați suma numerelor a si b, știind ca:
a=1+2+3+4+5+6
b=9×1+9×2+9×3+9×4+9×5+9×6

Answer 1

a = 1 + 2 + 3 + 4 + 5 + 6

a = 3 + 7 + 11

a = 10 + 11

a = 21

____________

b = 9 × 1 + 9 × 2 + 9 × 3 + 9 × 4 + 9 × 5 + 9 × 6

b = 9 × ( 1 + 2 + 3 + 4 + 5 + 6 )

b = 9 × ( 10 + 11 )

b = 9 × 21

b = 189

________

a + b = 21 + 189 = 210 → suma numerelor a si b

Answer 2

a=1+2+3+4+5+6

a=3+3+4+5+6

a=6+4+5+6

a=10+5+6

a=15+6=21

b=9•1+9•2+9•3+9•4+9•5+9•6

b=9+18+27+36+45+54

b=27+27+36+45+54

b=54+36+45+54

b=90+45+54

b=135+54=189

S=21+189=210