Question

a) \(\frac{4}{15}\times\frac{7}{9}+\frac{4}{15}\times\frac{2}{9}\)

b)\(\frac{13}{19}\times\frac{23}{11}-\frac{13}{19}\times\frac{8}{11}-\frac{13}{19}\times\frac{4}{11}\)

Giúp mình với nhé!

Answer 1

\(a.\) \(\frac{4}{15}.\frac{7}{9}+\frac{4}{15}.\frac{2}{9}\)

\(=\frac{4}{15}\left(\frac{7}{9}+\frac{2}{9}\right)\)

\(=\frac{4}{15}.\frac{9}{9}\)

\(=\frac{4}{15}.1\)

\(=\frac{4}{15}\)

\(b.\) \(\frac{13}{19}.\frac{23}{11}-\frac{13}{19}.\frac{8}{11}-\frac{13}{19}.\frac{4}{11}\)

\(=\frac{13}{19}\left(\frac{23}{11}-\frac{8}{11}-\frac{4}{11}\right)\)

\(=\frac{13}{19}.\frac{11}{11}\)

\(=\frac{13}{19}.1\)

\(=\frac{13}{19}\)

Answer 2

a)4/15 x(7/9+2/9)=4/15x1=4/15

b)13/19x(23/11-8/11-4/11)13/19x1=13/19

Answer 3

A) \(\frac{4}{15}x\frac{7}{9}+\frac{4}{15}x\frac{2}{9}\)

\(=\frac{28}{135}+\frac{8}{135}\)

\(=\frac{36}{135}=\frac{4}{15}\)

B) \(\frac{13}{19}x\frac{23}{11}-\frac{13}{19}x\frac{8}{11}-\frac{13}{19}x\frac{4}{11}\)

\(=\frac{299}{209}-\frac{104}{209}-\frac{52}{209}\)

\(=\frac{143}{209}\)

Answer 4

Mình nhầm câu B 

Kết quả là : \(\frac{13}{19}\)

Answer 5

A. 4/15

B. 13/19

Answer 6

a) \(\frac{4}{15}\cdot\frac{7}{9}+\frac{4}{15}\cdot\frac{2}{9}\)

\(=\frac{4}{15}\left(\frac{7}{9}+\frac{2}{9}\right)=\frac{4}{15}\cdot1=\frac{4}{15}\)

b) \(\frac{13}{19}\cdot\frac{23}{11}-\frac{13}{19}\cdot\frac{8}{11}-\frac{13}{19}\cdot\frac{4}{11}\)

\(=\frac{13}{19}\left(\frac{23}{11}-\frac{8}{11}-\frac{4}{11}\right)=\frac{13}{19}\cdot\frac{11}{11}=\frac{13}{19}\cdot1=\frac{13}{19}\)

Answer 7

a) \(=\frac{4}{15}.\left(\frac{7}{9}+\frac{2}{9}\right)\)

\(=\frac{4}{15}.1=\frac{4}{15}\)

b) \(=\frac{13}{19}.\left(\frac{23}{11}-\frac{8}{11}-\frac{4}{11}\right)\)

\(=\frac{13}{19}.\frac{11}{11}=\frac{13}{19}.1=\frac{13}{19}\)

Answer 8

a) \(\frac{4}{15}\)x \(\frac{7}{9}\)+ \(\frac{4}{15}\)x \(\frac{2}{9}\)

= \(\frac{4}{15}\)x   (  \(\frac{7}{9}\)+  \(\frac{2}{9}\))

= \(\frac{4}{15}\)x           \(1\)

= \(\frac{4}{15}\)

b)   \(\frac{13}{19}\)x \(\frac{23}{11}\)-  \(\frac{13}{19}\)x \(\frac{8}{11}\)- \(\frac{13}{19}\)x \(\frac{4}{11}\)

= \(\frac{13}{19}\)x ( \(\frac{23}{11}\)- \(\frac{8}{11}\)- \(\frac{4}{11}\))

= \(\frac{13}{19}\)x     \(1\)

=\(\frac{13}{19}\)

Chúc pạn hok tốt!

Answer 9

\(\frac{4}{15}\times\frac{7}{9}+\frac{4}{15}\times\frac{2}{9}\)

\(=\frac{4}{15}\times\left(\frac{7}{9}+\frac{2}{9}\right)\)

\(=\frac{4}{15}\times\frac{9}{9}=\frac{4}{15}\times1\)

\(=\frac{4}{15}\)

\(\frac{13}{19}\times\frac{23}{11}-\frac{13}{19}\times\frac{8}{11}-\frac{13}{19}\times\frac{4}{11}\)

\(=\frac{13}{19}\times\left(\frac{23}{11}-\frac{8}{11}-\frac{4}{11}\right)\)

\(=\frac{13}{19}\times1=\frac{13}{19}\)