\(\dfrac{2\times3\times5}{4\times9\times10}=\dfrac{2\times3\times5}{2^2\times3^2\times2\times5}=\dfrac{1}{2^2\times3}=\dfrac{1}{12}\)

\(\dfrac{2\text{×}3\text{×}5}{4\text{×}9\text{×}10}=\dfrac{2\text{×}3\text{×}5}{2\text{×}2\text{×}3\text{×}3\text{×}2\text{×}5}=\dfrac{1}{2\text{×}3\text{×}2}=\dfrac{1}{12}\)

\(\dfrac{2\times3\times5}{4\times9\times10}\)

\(=\dfrac{2\times3\times5}{2\times2\times3\times3\times5\times2}\)

\(=\dfrac{1}{2\times3\times2}=\dfrac{1}{12}\)

a. 6 x 5 = 30 

b.4 x 9 x 10 = 36 x 10 = 360 

4×9×102×3×5​

=\dfrac{2\times3\times5}{2\times2\times3\times3\times5\times2}=2×2×3×3×5×22×3×5​

=\dfrac{1}{2\times3\times2}=\dfrac{1}{12}=2×3×21​=121​
 

\(\dfrac{2.3.5}{2.5.7}=\dfrac{3}{7}\)

a)\(\frac{7x9x12}{6x14x18}=\frac{7x9x6x2}{6x7x2x9x2}=\frac{2}{2x2}=\frac{1}{2}\)

b) \(\frac{2x3x5}{4x9x10}=\frac{2x3x5}{2x2x3x3x2x5}=\frac{1}{2x2x3x5}=\frac{1}{60}\)

a=1/2
b=1/60

\(\frac{30\cdot25\cdot7\cdot8}{75\cdot8\cdot12\cdot14}\)

\(=\frac{2\cdot3\cdot5\cdot5\cdot5\cdot7\cdot8}{5\cdot3\cdot5\cdot8\cdot3\cdot2\cdot2\cdot2\cdot7}\)

\(=\frac{5}{3\cdot2\cdot2}\)

\(=\frac{5}{12}\)

\(\frac{2\cdot3\cdot5}{20\cdot6}\)

\(=\frac{2\cdot3\cdot5}{4\cdot5\cdot2\cdot3}\)

\(=\frac{1}{4}\)

\(\frac{30\times25\times7\times8}{75\times8\times12\times14}=\frac{6\times5\times25\times7\times8}{3\times25\times8\times6\times2\times7\times2}=\frac{5}{3\times2\times2}=\frac{5}{12}\)

\(\frac{2\times3\times5}{20\times6}=\frac{2\times3\times5}{4\times5\times3\times2}=\frac{1}{4}\)

~Học tốt ~~

tuui thách bạn tính bạn đó

\(\frac{2\times3\times5}{3\times5\times7}=\frac{2}{7}\)

2 x 3 x 5 / 3 x 5 x 7 = 2/7

Tk mk nha

Trả lời:

\(\frac{2\times3\times5}{3\times5\times7}=\frac{2}{7}\)

Gạch những thừa số chung có ở tử và mẫu thì ra.

\(\frac{165}{231}=\frac{3\times5\times11}{3\times11\times7}=\)\(\frac{5}{7}\)

 \(\frac{3}{7}\)

2x3x5   = 30 = 3 

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