1: \(=\dfrac{3}{8}\cdot\dfrac{5}{6}=\dfrac{15}{24}=\dfrac{5}{8}\)
2: \(=\dfrac{2}{3}+\dfrac{12}{42}=\dfrac{2}{3}+\dfrac{2}{7}=\dfrac{14+6}{21}=\dfrac{20}{21}\)
3: \(=\dfrac{24}{5}\cdot\dfrac{5}{12}=2\)
4: \(=\dfrac{1}{3}+\dfrac{3}{4}=\dfrac{4+9}{12}=\dfrac{13}{12}\)
`1/2xx3/4:6/5= 1/2 xx 3/4 xx 5/6 = 3/8 xx 5/6 =5/16`
`2/3+1/6:7/12 = 2/3 + 1/6 xx 12/7 = 2/3 + 2/7 = 14/21 + 6/21 = 20/21`
`8xx3/5:12/5= 8xx 3/5 xx 5/12 = 24/5 xx 5/12 = 2`
`4/9+3/4-1/3= (16/36 + 27/36 ) - 1/3 = 43/36 - 1/3 = 31/36`
`1/2xx3/4:6/5`
`=1/2xx3/4xx5/6`
`=3/8xx5/6`
`=15/48`
`=5/16`
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`2/3+1/6:7/12`
`=2/3+1/6xx12/7`
`=2/3+2/7`
`=14/21+6/21`
`=20/21`
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`8xx3/5:12/5`
`=8xx3/5xx5/12`
`=8xx1/4`
`=8/4`
`=2`
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`4/9+3/4-1/3`
`=(4/9-1/3)+3/4`
`=(4/9-3/9)+3/4`
`=1/9+3/4`
`=4/36+27/36`
`=31/36`