If you take 10% of 40 you get 4% however 40 is your total (100%) so therefore you would take the 4% multiply it by 2 and then you end up with 8% then you take 4% and divide it by 2 then add it on to your 8% then you end up with 10%
Total cards in a deck=52 Face cards =12 So probability of picking a face card is 12/52=3/13 Because probability of an event =chances of favourable outcomes/total number of outcomes
