Answer:
the final sample space is { 12,15,20,21,28,35}
Step-by-step explanation:
the sample space is the set of possible outcomes of the experiment , then the possible products are
3*7 = 21
3*5 = 15
3*4 = 12
4*7 = 28
4*5 = 20
5*7 = 35
since the product of 2 numbers is commutative, then we do not count the other possible combinations
therefore the final sample space is { 12,15,20,21,28,35}
Note:
to check that we have all the products , the possible combinations are
C(4,2)= 4!/(4-2)!*2!= 3*2*1 = 6
since we have considered 6 products , we are sure that our result is correct