`a)1/10 + 2/10 + 3/10 + 4/10 + 5/10 + 6/10 + 7/10 + 8/10 + 9/10`

`=(1/10+9/10)+(2/10+8/10)+(3/10+7/10)+(4/10+6/10)+5/10`

`=10/10 + 10/10+10/10+10/10+1/2`

`=1+1+1+1+1/2`

`=2+2+1/2`

`=4+1/2`

`=8/2+1/2`

`=9/2`

__

`13,25:0,5+13,25:0,25+13,25:0,125+13,25×6`

`=13,25×1/(0,5)+13,25×1/(0,25)+13,25×1/(0,125)+13,25×6`

`=13,25×(1/(0,5)+1/(0,25)+1/(0,125)+6)`

`=13,25×(2+4+8+6)`

`=13,25×20`

`=265`

`#QiN`

ban oi ban co chep nham de bai ko vay

sao bn viết ko có đấu vậy ghi vậy đâu ai hiểu  bn ghi cs đâu đi

ủa lớp 4 ko có bài này

13,25 : 0,5 + 13,25 : 0,25 + 13,25 : 0,125
=13.25*2+13.25*4+13.25*8
=13.25*(2+4+8)
=13.25*14
=185.5

\(13,25\div0,25+13,25\div0,25+13,25\div0,125+13,25\div0,25\)

\(=13,25\times2+13,25\times4+13,25\times8+13,25\times4\)

\(=13,25\times\left(2+4+8+2\right)\)

\(=13,25\times16\)

\(=212\)

P/s : Tính ra kết quả luôn == Sai thì thôi nha :>

\(13,25\div0,5+13,25\div0,25+13,25\div0,125-13,25\div0,25\)

\(=13,25\cdot2+13,25\cdot4+13,25\cdot8-13,25\cdot4\)

\(=13,25\left(2+4+8-4\right)\)

\(=13,25\cdot10\)

\(=132,5\)

`13,25 : 0,5 + 13,25 : 0,125 + 13,25 : 0,25`

`= 13,25 xx 2 + 13,25 xx8 + 13,25 xx 4`

`=  13,25 xx( 2+8+4)`

`=  13,25 xx14`

`= 185,5`

Em nhập đủ đề vào em hi

`=13,25xx2+13,25xx8+13,25xx4`

`=13,25xx(2+8+4)`

`=13,25xx14`

`=185,5`

tại sao lại nhân 4 và nhân8

\(13,25:(0,5+0,25+0,125)=13,25:0,875=15,14285714\) =)

TK

\(13,25:0,5+13,25:0,25+13,25:0,125\\ =13,25\times2+13,25\times4+13,25\times8\\ =13,25\times\left(2+4+8\right)\\ =13,25\times14\\ =185,5\)

\(13,25:0,5+13,25:0,125+13,25:0,125\\ =13,25\times2+13,25\times4+13,25\times8\\ =13,25\times\left(2+4+8\right)\\ =13,25\times14\\ =185,5\)

=13,25×2+13,25×4+13,25×8

=13,25×(2+4+8)

=13,25×14

=185,5