Răspuns:
2⁵¹+2⁵²+2⁵³= x•2⁵⁰
(1+2+2²)•2^51 = 2^50•x
(1+2+4)•2^51 = 2^50•x
x = 2^51•7:2^50
x = 7•2^(51-50)
x = 7•2
x = 14.
==EVERGREEN==
2⁵¹ + 2⁵² + 2⁵³ = x × 2⁵⁰
(1 + 2 + 2²)2⁵¹ = 2⁵⁰x
7 × 2⁵¹ = 2⁵⁰x
2⁵⁰x = 7 × 2⁵¹ → x = 7 × 2⁵¹ : 2⁵⁰
x = 7 × 2⁵¹-⁵⁰ = 7 × 2 = 14
