The top left and bottom right
Answer:
Step-by-step explanation:
No of ways in which 5 cards are chosen is 
No of ways in which at most 4 cards are spades
Total ways-5 spades

Probability that at most 4 cards are spade 



You do (12/300)x100 and it is going to give you the a answer
Out of the 3 points, only ABC are collinear. Hence, only ABC can be chosen. The chances of choosing ABC out of ABCD is 1/4. Hence, the probability is 25%.
Ok so the formula for this is A=1/2bh lets plug it in.
A=1/2*16*8
A=8*8
A=64 in^2