Question

a, 1/2 + 1/3 + 1/4     b,6/5 +4/3 + 9/7       c, 2/3 + 8/9 -5/6           d.  2/3 + 3/4 x 4/5 

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Answer 1

`1/2 + 1/3 + 1/4`

` = 6/12 + 4/12 + 3/12`

` = (6 + 4+3)/12`

` = 13/12`

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`6/5 + 4/3 + 9/7`

` = 126/105 + 140/105 + 135/105`

` = (126 + 140 + 135)/105`

` = 401/105`

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`2/3 + 8/9 - 5/6`

` = 12/18 + 16/18 - 15/18`

` = (12+16-15)/18`

`= 13/18`

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`2/3 + 3/4 xx 4/5`

`= 2/3 + 3/5`

` = 10/15 + 9/15`

`=(10+9)/15`

` = 19/15`

Answer 2

`1/2+1/3+1/4`

`=(1xx3)/(2xx3)+(1xx2)/(3xx2)+1/4`

`=3/6+2/6+1/4`

`=5/6+1/4`

`=(5xx4)/(6xx4)+(1xx6)/(4xx6)`

`=20/24+6/24`

`=26/24`

`=13/12`

`6/5+4/3+9/7`

`=(6xx3)/(5xx3)+(4xx5)/(3xx5)+9/7`

`=18/15+20/15+9/7`

`=38/15+9/7`

`=266/105+135/105`

`=401/105`

`2/3+8/9-5/6`

`=(2xx9)/(3xx9)+(8xx3)/(9xx3)-5/6`

`=18/27+24/27-5/6`

`=42/27-5/6`

`=14/9-5/6`

`=84/36-45/36`

`=39/36`

`=13/18`

`2/3+3/4xx4/5`

`=2/3+3/5`

`=(2xx5)/(3xx5)+(3xx3)/(5xx3)`

`=10/15+9/15`

`=19/15`

Answer 3

\(\dfrac{1}{2}+\dfrac{1}{3}+\dfrac{1}{4}=\dfrac{6}{12}+\dfrac{4}{12}+\dfrac{3}{12}=\dfrac{13}{12}\)

\(\dfrac{6}{5}+\dfrac{4}{3}+\dfrac{9}{7}=\dfrac{126}{105}+\dfrac{35}{105}+\dfrac{135}{105}=\dfrac{296}{105}\)

\(\dfrac{2}{3}+\dfrac{8}{9}-\dfrac{5}{6}=\dfrac{24}{36}+\dfrac{32}{36}-\dfrac{30}{36}=\dfrac{13}{18}\)

\(\dfrac{2}{3}+\dfrac{3}{4}\times\dfrac{4}{5}=\dfrac{2}{3}+\dfrac{12}{20}=\dfrac{19}{15}\)

Answer 4

a) 1 /  2 + 1 / 3 + 1 / 4 = 0,5 + 0,33333333333 + 0,25 = 1,08333333333

b) 6 / 5 + 4 / 3 + 9 / 7 = 1,2 + 1,33333333333 + 1,28571428571 = 3,81904761905 

c) 2 / 3 + 8 / 9 - 5 / 6 = 0,66666666666 + 0,88888888888 - 0,83333333333 = 0,722222222222

d) 2 / 3 + 3 / 4 * 4 / 5 = 0,66666666666 + 0,75 * 0,8 = 1,26666666667

Answer 5

a) \(\dfrac{1}{2}+\dfrac{1}{3}+\dfrac{1}{4}\)

\(=\)  \(\dfrac{6}{12}+\dfrac{4}{12}+\dfrac{3}{12}\)

\(=\)\(\dfrac{13}{12}\)

b) \(\dfrac{6}{5}+\dfrac{4}{3}+\dfrac{9}{7}\)

\(=\)\(\dfrac{38}{15}+\dfrac{9}{7}\)

\(=\)\(\dfrac{401}{105}\)

c) \(\dfrac{2}{3}+\dfrac{8}{9}-\dfrac{5}{6}\)

\(=\)   \(\dfrac{12}{18}+\dfrac{16}{18}-\dfrac{15}{18}\)

\(=\)   \(\dfrac{13}{18}\)

d)   \(\dfrac{2}{3}+\dfrac{3}{4}\times\dfrac{4}{5}\)

\(=\)   \(\dfrac{2}{3}+\dfrac{3}{5}\)

\(=\)   \(\dfrac{19}{15}\)

Answer 6

a) = 13/12

b) = 401/105

c) = 13/18

d) = 19/15

Answer 7

a, 1/2+1/3+1/4
=6/12+4/12+3/12
=13/12