Answer: the total number of audience members is 1800
Explanation:
Let x represent the total number of audience members at the concert.
At the concert, 20% of the audience members were teenagers. This means that the number if teenagers at the concert would be expressed as
20/100 × x = 0.2 × x = 0.2x
If the numbers of teenagers at the concert was 360, it means that
0.2x = 360
Dividing the left hand side and the right hand side of the equation by 0.2, it becomes
0.2x/0.2 = 360/0.2
x = 1800