Let bᵢ > 1 for i = 1, 2, …, 101. Suppose logₑ b₁, logₑ b₂, …, logₑ b₁₀₁ are in Arithmetic Progression (A.P.) with the common difference logₑ 2. Suppose a₁, a₂, …, a₁₀₁ are in A.P. such that a₁ = b₁ and a₅₁ = b₅₁. If t = b₁ + b₂ + … + b₅₁ and s = a₁ + a₂ + … + a₅₁, then
bi>1,i=1,2,…,101
logeb1,logeb2,…,logeb101 in A.P.
common difference d=loge2
a1=b1,a51=b51
t=b1+b2+…+b51
s=a1+a2+…+a51
logebi=logeb1+(i−1)loge2
⇒ bi=b1⋅2i−1
so bi is a G.P. with common ratio 2
b51=b1⋅250
d=50a51−a1=50b1(250−1)
ai=a1+(i−1)d
ai=b1+(i−1)50b1(250−1)
the chord ai lies above the convex bi
ai≥bi(1<i<51)
s−t=∑i=151(ai−bi)>0
∴ s>t
t=b1+b12+…+b1250
t=b12−1251−1=b1(251−1)
s=251(a1+a51)=251b1(1+250)
s−t=b1(253+247⋅250)>0
a101=a1+100d
=b1+100⋅50b1(250−1)
=b1(251−1)
b101=b1⋅2100
a101=b1(251−1)<b1⋅2100=b101
∴ a101<b101
s>tanda101<b101
Answer: (2)