Sequence L1, L2, ...L10, and M1 to M10, where L is integers and M is remainder of L divided by 2. What is the sum of M?
1) Sum of L = 100
2) Six terms of L are even
Notice, value of M can only be 0 or 1
1.sum of L is even ----> the number of
odd terms in the L sequence is even
..that is to say, the number of odd terms can be 0,2,4,6,8,10 ---> the sum of M sequence can be 0,2,4,6,8,10 --->insuff
2. ----> 4 terms of L are odds ...each odd term forms a term M of M sequence with the value of 1 ---> the sum of M sequence is 4*1=4 --->suff