a1+a2+a3+a4........+an=350--------------1)Akansha wrote:If each term in the series a1 + a2 + ... 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
OA is C
as here each term is either 7 or 77, i.e. a multiple of 7,
so above expression in 1) can be reduced to;
7(k1+k2+k3+k4+k5+.....kn)=350;
k1+k2+k3+k4+k5+.....kn=50; here k1,k2,k3,...kn is either 1 or 11;
now if we work with options, only option that will result in sum of 50 is C, and that when we have 39 1's and one 11. hence answer should be C
