3 per 4 + 5 per 6 - 7 per 8 ÷ 5 1 per 4

3/4 + 5/6 - 7/8 ÷ 5 1/4=

3/4+5/6-(7/8 ÷ 21/4)=

3/4 + 5/6 - 7/8 × 4/21=

3/4 + 5/6 - 28/168=

3/4 + 5/6 - 1/6 =

9/12 + 10/12 - 2/12=

19/12 - 2/12 = 17/12

= 1 5/12

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