Each of A, B, C and D is a positive integer with the proviso that A ≤ B ≤ C ≤ D ≤ 20.
Determine the total number of quadruplets (A, B, C, D) such that A*B*C*D is divisible by 50.
(In reply to
Solution by Praneeth)
TOTALLY WRONG:
Case 1: 4 chosen from p
NOT NECESSERALLY DISTINCT,BUT
MUST INCLUDE 5^2 AND 2
So:
20,20,20,20 15,15,15,20 10,15,15,20 10,10,15,20
10,10,10 ,10, 5,10,10,10 ETC ARE OK
5,5,5.15 5,5,5.5 ARE not OK
Count them ,it is more than 1
So are other cases