Question

2+4+6+8+.........+630=


cat fac?

Answer 1

Răspuns

Explicație pas cu pas:

2 + 4 + 6 + 8 + ...... + 630 = 99 540

= 2 x ( 1 + 2 + 3 + 4 + ...... + 315 ) =

= 2 x 315 x ( 1 + 315 ) : 2 =

= 315 x 316 =

= 99 540

Answer 2

2 + 4 + 6 + 8 + ... + 630 =
2 × ( 1 + 2 + 3 + ... + 315 ) =
2 × ( 315 × 316 : 2 ) =
2 × ( 99 540 : 2 ) =
2 × 49 770 = 99 540