Question

91+92+93+94+95+96+97+98+99= bao nhiêu

Answer 1

91+92+93+94+95+96+97+98+99

=(91+99)+(92+98)+(93+97)+(94+96)+95

=   190   +   190   +   190   +   190   + 95

=                    760                    +     95

=  855

Answer 2

Theo mình thì là:857

Answer 3

= (99 + 91) + ( 98 + 92 ) + ( 97+ 93 ) + ( 94 + 96 ) + 95

= 190 + 190 + 190 +190 +95

= 760 + 95 

= 855

Answer 4

= (91+99)+(92+98)+(93+97)+(94+96)+95

=190+190+190+190+95

=380+380+95

=760+95

=855