5 7/8-2 2/3+4 5/6=7 +(7/8 -2/3 + 5/6)=7+(21/24-16/24+20/64)= 7 25/24=
= 8 1/24
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= 9 +(5/7 +3/4 -5/8) = 9 +(40/56+ 42/56-35/56)=9 63/56=10 7/56=
= 10 1/8
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= 7 +(8/15+5/18-3/5)=7+(48/90+25/90-54/90)= 7 19/90
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= 15 + (8/12 + 7/18)=15 +(72/108+63/108) =7 135/108 =8 27/108 =
= 8 1/4
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= 11 +(7/16 +3/10) = 11 +(35/80+24/80)=11 59/80