Question

10+20+30+40+50+60+70+80+90=

Answer 1

10+20+30+40+50+60+70+80+90

=(10+90)+(20+80)+(30+70)+(40+60)+50

=100+100+100+100+50

=450

giùm mình nha!

Answer 2

10+20+30+40+50+60+70+80+90= 450 nha bn ~

Answer 3

10+20+30+40+50+60+70+80+90=470

Answer 4

10 + 20 + 30 + 40 + 50 + 60 + 70 + 80 + 90 

= ( 10 + 90 ) + ( 20 + 80 ) + ( 30 + 70 ) + ( 40 + 60 ) + 50 

= 100 + 100 + 100 + 100 + 50

= 100 x 4 + 50

= 400 + 50

= 450

Answer 5

ket pua =450

Answer 6

10+20+30+40+50+60+70+80+90=?

=> 450

Chúc bạn học tốt

Answer 7

10+20+30+40+50+60+70+80+90=?

Số cần tìm là:

10+20+30+40+50+60+70+80+90=450

Đáp số:450

Answer 8

10+20+30+40+50+60+70+80+90=...

Xét tổng trên ta có (90-10)/10+1=9 số hạng

\(\Rightarrow\)10+20+30+40+50+60+70+80+90

=(90+10)*9/2=450

Answer 9

Số cần tìm là :

10+20+30+40+50+60+70+80+90= 450

                      Đ/s : 450 

:)

Answer 10

10+20+30+40+50+60+70+80+90=

=30+30+40+50+60+70+80+90

=60+40+50+60+70+80+90

=100+50+60+70+80+90

150+60+70+80+90

=210+70+80+90

=280+80+90

=360+90

=450