\(\dfrac{17}{30}\)m²

a:\(\dfrac{33}{44}=\dfrac{3}{4}\\ MSC:8\\ \dfrac{3}{4}=\dfrac{3\times2}{4\times2}=\dfrac{6}{8};\dfrac{2}{8}\)

b:\(\dfrac{9}{12}=\dfrac{3}{4};\dfrac{24}{36}=\dfrac{7}{9}\\ MSC:72\\ \dfrac{3}{4}=\dfrac{3\times18}{4\times18}=\dfrac{54}{72};\dfrac{7}{9}=\dfrac{7\times8}{9\times8}=\dfrac{56}{72};\dfrac{3}{8}=\dfrac{3\times9}{8\times9}=\dfrac{27}{72}\)

mong có ai giúp

\(\dfrac{96}{54}=\dfrac{16}{9}\)

\(\dfrac{16}{9}\)

>

>

>

=

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\(\frac{12\times8\times7}{12\times21\times16}\)

\(=\frac{8\times7}{3\times7\times2\times8}\)

\(=\frac{1}{6}\)

Đúng

đúng

Bài 2: Tìm x, biết:

x - 5/15 = 42/105

X=87/105

8/ x + 3 = 56/91

Ko nhớ

Bài 3: Cho các phân số 9/10, 15/18, 21/15, 5/4, 16/4, 256/112

a) Phân số nào tối giản?9/10,5/4

b) Rút gọn những phân số chưa tối giản.15/18=5/6 21/15=7/5 256/112=128/56=64/28=32/14=16/7

Bài 2 

\(x-\frac{5}{15}=\frac{42}{105}\)

\(x=\frac{42}{105}+\frac{5}{15}\)

\(x=\frac{42}{105}+\frac{5\times7}{15\times7}\)

\(x=\frac{42}{105}+\frac{35}{105}\)

\(x=\frac{77}{105}\)

Rút gọn \(\frac{77}{105}=\frac{11}{15}\)

\(\frac{4}{5}\)

\(\left(\dfrac{8}{15}-\dfrac{7}{15}\right):\dfrac{11}{2}\)

\(\dfrac{1}{15}x\dfrac{11}{2}=\dfrac{11}{30}\)

\(\dfrac{8}{15}:\dfrac{2}{11}-\dfrac{7}{15}:\dfrac{2}{11}\)

\(=\left(\dfrac{8}{15}-\dfrac{7}{15}\right).\dfrac{11}{2}\)

\(=\dfrac{1}{15}.\dfrac{11}{2}=\dfrac{11}{30}\)

\(=\dfrac{10}{20}=\dfrac{1}{2}\)

\(=\dfrac{2.2.5.2.3}{3.5.2.2.2.2}=\dfrac{1}{2}\)