If each term in the sum a1+a2+a3+.....+an is either 7 or 77

[imane81]

Your help in this one is much appreciated..

If each term in the sum a1+a2+a3+.....+an is either 7 or 77 and the sum equals 350, which of the following could be equal to n?
A. 38
B.39
C.40
D.41
E.42

[ajith]

Your help in this one is much appreciated..

If each term in the sum a1+a2+a3+.....+an is either 7 or 77 and the sum equals 350, which of the following could be equal to n?
A. 38
B.39
C.40
D.41
E.42

Already discussed please search

[harsh.champ]

Your help in this one is much appreciated..

If each term in the sum a1+a2+a3+.....+an is either 7 or 77 and the sum equals 350, which of the following could be equal to n?
A. 38
B.39
C.40
D.41
E.42

In short I would say after adding each term the no. in the units place will go in a series like 7,4,1,8... which becomes 0 for the 10th term.Hence,the answer has to be a multiple of 10. So,C.

[shashank.ism]

check the appropriate solution in this thread..
https://www.beatthegmat.com/if-each-term ... 13856.html