Question

S3二什3+5+....+275
dau coroana​

Answer 1

n=(u-p):r+1

n=(275-1):2+1

n=274:2+1

n=137+1

n=138

S3=(u+p)×n:2

S3=(275+1)×138:2

S3=276:2×138

S3=138×138

S3=19044