题目

In meditation(冥想)，people sit quietly and focus their attention on their breath .As they breathe in and out, they attend to their feelings .As thoughts go through their minds, they let them go. Breathe .Let go .Breathe .Let go. According to a recent study at the Insight Meditation Society in Barre, Massachusetts. Three months of training in this kind of meditation causes a market change in how the brain allocates(分配) attention. It appears that the ability to let go thoughts that come into mind frees the brain to attend to more rapidly changing things and events in the outside world. 5．先列比例再解比例．（1）等号左端的比是6：x，等号右端的前项和后项分别是4.5和2.5．（2）6与$\frac{1}{3}$的比，等于一个数与$\frac{1}{3}$和$\frac{1}{4}$的和的比，求这个数．