\(\dfrac{1717}{1515}=\dfrac{1717:101}{1515:101}=\dfrac{17}{15}\)

ấy dấu gạch kiểu gì thế

\(\frac{1717}{1919}.\frac{303}{1818}+\frac{1717}{1919}.\frac{1515}{1818}\)

\(=\frac{1717}{1919}.\left(\frac{303}{1818}+\frac{1515}{1818}\right)\)

\(=\frac{1717}{1919}.1\)

\(=\frac{17}{19}\)

Dấu "." là dấu " x " 

học tốt!!!

\(A=\frac{17\cdot101}{19\cdot101}\cdot\frac{1\cdot303}{6\cdot303}+\frac{17\cdot101}{19\cdot101}\cdot\frac{5\cdot303}{6\cdot303}\) 

\(=\frac{17}{19}\cdot\frac{1}{6}+\frac{17}{19}\cdot\frac{5}{6}\) 

\(=\frac{17}{19}\cdot\left(\frac{5}{6}+\frac{1}{6}\right)\) 

\(=\frac{17}{19}\cdot1\) 

\(=\frac{17}{19}\)

\(=\dfrac{17}{41}+\dfrac{15}{23}=\dfrac{1006}{943}\)

\(\dfrac{1717}{4141}+\dfrac{1515}{2323}=\dfrac{17}{41}+\dfrac{15}{23}=\dfrac{601}{322}\)

=601/322

Kết quả rút gọn lần lượt là:  1 2 ; − 3 8 ; 1 2 ; 2 3 ; 3 2 ; − 15 17

1515/1616=15/16=30/32

1717/3232=17/32

mà 30/32>17/32

nên 1515/1616>1717/3232

\(\dfrac{54}{72}=\dfrac{3}{4}\)
\(\dfrac{92}{100}=\dfrac{23}{25}\)
\(\dfrac{126}{165}=\dfrac{42}{55}\)
\(\dfrac{1717}{1515}=\dfrac{17}{15}\)

54 phần 72=`54/72=3/4`

92 phần 100=`92/100=23/25`

126 phần 165=`126/165=42/55`

1717 phần 1515=`1717/1515=17/15`

Đề bài kiểu gì vậy?VIết rõ hơn đi

rối mắt á

1414+1515+1616+1717+1818+1919

2020+2121+2222+2323+2424+2525