a÷ 2/3=1/4 => aㄨ3/2=1/4 => a=1/4÷3/2 => a=1/4X2/3 => a=2/12 => a=1/6
b÷1又1/3=1/4 => b÷4/3=1/4 =>bX3/4=1/4 => b=1/4÷3/4 => b=1/4X4/3 => b=4/12=1/3
a+b=1/6+1/3=1/6+2/6=3/6=1/2
粗心大意XDD
4. 若 ,則下列敘述何者正確? (A) ..-阿摩線上測驗