Expression : $$(2^{51}+2^{52}+2^{53}+2^{54}+2^{55})$$
= $$2^{51}(1+2+2^2+2^3+2^4)$$
= $$2^{51}(1+2+4+8+16)$$
= $$2^{51} \times 31$$
Thus, the above expression is divisible by $$31k$$ and the only option that is divisible by 31 = 124
=> Ans - (C)
Create a FREE account and get: