Let T = number of TVs

R = number of Radios

From the information given T + R <= 285

and R = (1/2)T

So, substituting

T + (1/2)T <= 285

or (3/2)T <= 285

and T <= 190

if T = 190, then R = 95 and if T = 2 then R = 1

So radios could range (practically since you cannot have half a radio! ) from 1 to 95