At the start of the video, the members announced, "We will be number one!" as they took their places.  The rules were as follows: 1) Don't be intimidated by the song changes, 2) Make sure to be in sync with the music, 3) 5 tries in total, minus 10 points for every mistake, 4) additional 50 points for completing bonus mission.

They were given a bonus mission to show off their signature 'bang bang' move shooting at the balloons.  The girls then took turns aiming at the target as the music began.

Dressed in military attire, the girls were in sync while performing their hit song.  Members Sowon and SinB also demonstrated their tactical skills with their signature 'bang bang' move.

Check out their fun time on 'Let's Dance' above!

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