Sonia bought 30 t shirts at a clothing store. 20% of the t shirts were blue and 1/2 of the t shirts were black. How many of the t shirts were neither black or blue?

9 T-Shirts

Step-by-step explanation: There are 30 t shirts. 20% of the t shirts were blue and 1/2 of the t shirts were black. 20% is equivalent / the same as 20/100 and simplified, 1/5. 1/2 black + 1/5 blue = 70/100 black and blue. This leaves 30/100 (30%) remaining t shirts (neither black or blue). This leaves us to find 30% of 30 (shirts). 30% of 30 equals 9. 30/100 = 9/30.