1+2+3+4+5+6+7+8+9+10
=(1+9)+(2+8)+(3+7)+(4+6)+10+5
=10+10+10+10+10+5
=50+5
=55
1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10
= ( 1 + 9 ) + ( 2 + 8 ) + ( 3 + 7 ) + ( 4 + 6) + 5 + 10
= 1 + 1 + 1 + 1 + 5 + 10
= 19
k nha mình k lại
=(1+9)+(2+8)+(3+7)+(4+6)+5
= 10 + 10+10+10+5
= 55
+ 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10
= ( 1 + 9 ) + ( 2 + 8 ) + ( 3 + 7 ) + ( 4 + 6) + 5 + 10
= 10 + 10 + 1 0+ 10 + 5 + 10
= 10 x 4 + 5 + 10
= 50 + 5
= 55
1+2+3+4+5+6+7+8+9+10
=(1+9)+(2+8)+(3+7)+(4+6)+10+5
=10+10+10+10+10+5
=50+5
=55
mik nha Nobita Kun
1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10
= ( 1 + 9 ) + ( 2 + 8 ) + ( 3 + 7 ) + ( 4 + 6 ) + 5 + 10
= 10 + 10 + 10 + 10 + 5 + 10
= 40 + 5 + 10
= 55
k nhamk k laij
= ( 1 + 9 ) + ( 2 + 8 ) + ( 3 + 7 ) + ( 4 + 6 ) + 10 + 5
= 10 + 10 + 10 + 10 + 10 + 5
= 50 + 5
= 55
= (9+1) + (8+2) + (7+3) + (6+4) + 5 +10
= 10 + 10 + 10 + 10 + 5 + 10
= 40 + 5 + 10
= 45 + 10
= 55
1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 =55
k nha Nobita Kun
= ( 1+9)+(2+8)+(7+3)+(6+4)+10+5
=10+10+10+10+10+5
=55
l-i-k-e nha!!^^)
1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10
= ( 1 + 9 ) + ( 2 + 8 ) + ( 3 + 7 ) + ( 4 + 6) + 5 + 10
= 1 + 1 + 1 + 1 + 5 + 10
= 19