At a concert 20% of the people are wearing black dresses or suits,1/4 are wearing navy, 0.35 are wearing brown ,and the rest are wearing a variety of colors. write the percent, fraction, and decimal for the rest of the other people that are wearing other colors

Let us assume the total number of people at the concert = x
Then
Number of people wearing black dresses or suits = (20/100) * x
                                                                                = x/5
Number of people wearing navy = (1/4) * x
                                                    = x/4
Number of people wearing brown = 0.35 * x
                                                       = (35/100) * x
                                                       = 7x/20
So
The number of people wearing a variety of colors = x - [(x/5) + (x/4) + (7x/20)]
                                                                                = x - [ (4x + 5x +7x)/20]
                                                                                = x - (16x/20)
                                                                                 = x - (4x/5)
                                                                                 = (5x - 4x)/5
                                                                                 = x/5
So it can said from the above deduction that 1/5th of the total number of people were wearing variety of color dresses.

The linear equation is: y=ax+b