\(\dfrac{42\cdot32}{12\cdot14\cdot16}\)(Dấu . là dấu nhân)
\(=\dfrac{7\cdot6\cdot8\cdot2\cdot2}{6\cdot2\cdot7\cdot2\cdot8\cdot2}\)
\(=\dfrac{1}{2}\)
 

\(\dfrac{42.32}{12.14.16}=\dfrac{1344}{2688}=\dfrac{1}{2}\)

`2424/4545=(2424:303)/(4545:303)=8/15`

= 8/15 

Nhớ tick nha

\(\dfrac{26}{39}=\dfrac{26:13}{39:13}=\dfrac{2}{3}\)
\(\dfrac{38}{57}=\dfrac{38:19}{57:19}=\dfrac{2}{3}\)

\(\dfrac{26}{39}=\dfrac{26:13}{39:13}=\dfrac{2}{3}\)

\(\dfrac{38}{57}=\dfrac{38:19}{57:19}=\dfrac{2}{3}\)

\(\dfrac{7}{5}-\dfrac{5}{16}\)
\(=\dfrac{112}{80}-\dfrac{25}{80}\)
\(=\dfrac{87}{80}\)

`7/5 - 5/16`

`=112/80 -25/80`

`=87/80`

120 trang

\(\dfrac{3}{16};\dfrac{5}{24};\dfrac{21}{56}\)

\(\dfrac{21}{56}=\dfrac{3}{8}=\dfrac{18}{48}\)

\(\dfrac{5}{24}=\dfrac{10}{48}\)

\(\dfrac{3}{16}=\dfrac{9}{48}\)

Ta quy đồng được thành: \(\dfrac{9}{48};\dfrac{10}{48};\dfrac{18}{48}\)

\(\dfrac{3}{16}\text{=}\dfrac{3\times21}{16\times21}\text{=}\dfrac{63}{336}\)

\(\dfrac{5}{24}\text{=}\dfrac{5\times14}{24\times14}\text{=}\dfrac{70}{336}\)

\(\dfrac{21}{56}\text{=}\dfrac{21\times6}{56\times6}\text{=}\dfrac{126}{336}\)

Bằng 2023

\(3\times145+3\times\dfrac{55}{6}\times215+6\times85\)

\(=3\times145+3\times\dfrac{55}{6}\times215+3\times2\times85\)

\(=3\times\left(145+\left(\dfrac{55}{6}\times215\right)+\left(2\times85\right)\right)\)

\(=3\times\left(145+\dfrac{11825}{6}+170\right)\)

\(=3\times\dfrac{13715}{6}=6857,5\)

3*(145+55):6*(215+85)

3*200:6*300

600:6*300

100*300=30000

\(a.\dfrac{11}{10}\text{=}\dfrac{11\times3}{10\times3}\text{=}\dfrac{33}{30}\)

\(\dfrac{19}{30}\) giữ nguyên

\(b.\dfrac{23}{38}\text{=}\dfrac{23\times3}{38\times3}\text{=}\dfrac{69}{114}\)

\(\dfrac{14}{57}\text{=}\dfrac{14\times2}{57\times2}\text{=}\dfrac{28}{114}\)

Sos