Given : y = -0.1x + 1 where, y = percentage, x = time in seconds Now, substituting the values from the question into the equation, we get, 50% = -0.1x +1 .50 - 1 = -0.1x -.50 = -0.1x -.50 / (-0.1) = x 5 = x x = 5 So, the time taken to download 50% of the song is 5 seconds