Question

(1+2+3+.....+49+50+49+48+....+3+2+1)=? ​

Answer 1

Required Sum =

[tex]2\left ( \frac{x\left ( x+1 \right )}{2} \right )+50 [/tex]

$=>\frac{2\times 49\times 50}{2}+50=2500$

Answer 2

50(50+1)/2

50×51/2

25×51

1275

1275+1274

2549