1.3.6x31又5分之2+43.9x6又5分之2+6
=3.6×（31+2/5）+43.9×(6+2/5)+6
=3.6×31+3.6×2/5+43.9×6+43.9×2/5+6
=111.6+263.4+(3.6+43.9)×0.4+6
=375+19+6
=375+25
=400;
2.(9又7分之2+79又9分之2）
=9+2/7+79+2/9
=88+18/63+14/63
=88+32/63;
=88又63分之32；
3.12+23+23+34+45+56+67分之1.2+2.3+3.4+4.5+5.6+6.7
=(1.2+2.3+3.4+4.5+5.6+6.7)÷(1.2+2.3+3.4+4.5+5.6+6.7)×10
=1/10;
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