Xian plans to run 20 laps around a track. Each lap is 400 yards. So far Xian has to run 1680 yards around the track. What percentage of the run has Xian completed.

20 laps ... each lap is 400 yds ... 20 x 400 = 8000 yds

1680/8000 = 0.21 ... multiply by 100 to get ur percent = (0.21 x 100) = 21%

First convert laps to yards.

20 * 400 = 8000 yards. This is the total amount of yards that Xian plans to run.

He has already completed 1680 of the 8000, so divide 1680/8000 and get. 21, then multiply by 100 to get your percent. 21%