Tính bằng hai cách:
(6/11+5/11)×3/7 3/5×7/9+3/5×2/9
(6/74/7):2/5 8/15:2/11+7/15:2/11
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Giải đáp+Lời giải và giải thích chi tiết:Tính bằng hai cách:(6/11+5/11)×x3/73/5×x7/9+3/5×x2/9(6/7-4/7):2/58/15:2/11+7/15:2/11a.(6/11+5/11)×x3/7=1×x3/7=3/7(6/11+5/11)×x3/7=6/11×x3/7+5/11×x3/7=18/77+15/77=33/77=37b.3/5×7/9+3/5×2/9=21/45+6/45=27/45=3/53/5×7/9+3/5×2/9=3/5×(7/9+2/9)=3/5×1=3/5c.(6/7−4/7):2/5=2/7×5/2=10/14(6/7−4/7):2/5=6/7:2/5−4/7:2/5=6/7×5/2−4/7×5/2=30/14−20/14=10/14d.8/15:2/11+7/15:2/11=8/15×1/12+7/15×11/2=88/30+77/30=165/30=11/28/15:2/11+7/15:2/11=(8/15+7/15):2/11=1×11/2=11/2
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1)C1:(6/11+5/11)xx3/7=11/11xx3/7=1xx3/7=3/7C2:(6/11+5/11)xx3/7=6/11xx3/7+5/11xx3/7=18/77+15/77=33/77=3/72)C1:3/5xx7/9+3/5xx2/9=21/45+6/45=27/45=3/5C2:3/5xx7/9+3/5xx2/9=3/5xx(7/9+2/9)=3/5xx9/9=3/5xx1=3/53)C1:(6/7-4/7):2/5=2/7:2/5=2/7xx5/2=10/14=5/7C2:(6/7-4/7):2/5=6/7:2/5-4/7:2/5=6/7xx5/2-4/7xx5/2=30/14-20/14=10/14=5/74)C1:8/15:2/11+7/15:2/11=8/15xx11/2+7/15xx11/2=88/30+77/30=165/30=33/6=11/2C2:8/15:2/11+7/15:2/11=(8/15+7/15):2/11=15/15:2/11=1:2/11=1xx11/2=11/2
