20 12 On September 7th, an earthquake occurred at the junction of yiliang county, Zhaotong City, Yunnan Province and Bijie Prefecture, Guizhou Province. The earthquake caused landslides and paralyzed

20 12 On September 7th, an earthquake occurred at the junction of yiliang county, Zhaotong City, Yunnan Province and Bijie Prefecture, Guizhou Province. The earthquake caused landslides and paralyzed the expressway connecting the two places. (1) Let the speed of team B be x km/h, then the speed of team A is 3/2X+5, so.

2(3/2X+5)+2.5X = 176- 1，

The solution is X=30,

3/2X+5=50，

∴ The speeds of Party A and Party B are 50km/h and 30km/h respectively.

(2) Assuming that B digs Y kilometers per hour, it needs

6 * 1/ 12+5.5 * Y = 1，

The solution is y =111,

When1÷11=1/

∴ If only Team B dredges this road, it will take 1 1 hour to complete it.