Problems in the Pursuit of Mathematical Olympics in Primary Schools

Solution:

3.6 km = 3,600 m

Because Xiao Wang stops every 5 minutes 1 minute, so

Xiao Wang's distance of 6 minutes in each row is 200 * 5 =1000 m.

Xiao Zhang's 6-minute journey for each line is: 80 * 6 = 480m.

Every country takes 6 minutes for Xiao Wang to catch up with Xiao Zhang:1000-480 = 520m.

3600/(1000-480) = 6 ... 480m.

After 6 6 minutes, Xiao Wang overtook Xiao Zhang by 520 * 6 = 3 120m or 3600-480 = 3 120m.

At this point, Xiao Wang still has 480 meters to catch up with Xiao Zhang, so

Xiao Wang needs 480m to catch up with Xiao Zhang: 480/(200-80) = 4 minutes.

It takes 6 * 6+4 = 40 minutes for Xiao Wang to catch up with Xiao Zhang.