For the sixth time, the train increased its speed from 180 km / h

For the sixth time, the train increased its speed from 180 km / h

The sixth railway speed increase was implemented, and the running speed reached 200 km for the first time, including 250 km for some sections of the Beijing Harbin, Beijing Guangzhou and Beijing Kowloon lines. This railway speed increase involves Beijing Harbin, Beijing Kowloon, Beijing Guangzhou, Beijing Shanghai, Longhai, Lanxin, Zhejiang Jiangxi, Jiaoji and other major trunk lines,

On April 8, 2007, China's train speed was increased for the sixth time. After the increase, the average train speed on Beijing Guangzhou line was 120 kilometers per hour, which was 1 / 4 faster than before
How many kilometers per hour do you travel on the train

120/(1+1/4)=96
96 kph before speed up

The train can travel 1272km in 6 hours. After the speed increase, the train can complete the same journey in 5 hours, and the speed is increased by ()%

(1272÷5-1272÷6)÷(1272÷6)
=1272x(1/5-1/6)÷1272x6
=6x(1/5-1/6)
=6/5-1
=1/5
=20%
The train can travel 1272km in 6 hours. After the speed increase, it can complete the same journey in 5 hours, and the speed is increased by (20)%

After the sixth train speed increase in China, the average train speed on a truck trunk line has increased from 160 km / h to 200 km / h. what percentage has the train speed increased?

160（x＋1）＝200