since the problem says “lamborghini OR corvette” you need to add the probability amount of both cars together. There are 2 lamborghinis and 4 corvettes, so 2+4=6. Now, put this number over the total amount of all cars. 6+2+4+8+12=32. So, the probability will be 6/32 which simplifies to 3/16. In decimal form this is .1875, and in percent form this is 18.75% (move the decimal 2 places to the right)