7/9 – 15/10 =1 8/24 – 10/6 =​

7/9 – 15/10

= 7/9 – 3/2

= 14/18 – 27/18

= (14 – 27)/18

= -13/18

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1 8/24 – 10/6

= 32/24 – 10/6

= 4/3 – 10/6

= 4/3 – 5/3

= (4 – 5)/3

= -1/3