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Find the sum of the products of the corresponding terms of the sequences 2, 4, 8, 16, 32 and 128, 32, 8, 2, 1/2.

The necessary aggregate \[=~2\text{ }x\text{ }128\text{ }+\text{ }4\text{ }x\text{ }32\text{ }+\text{ }8\text{ }x\text{ }8\text{ }+\text{ }16\text{ }x\text{ }2\text{ }+\text{ }32\text{ }x\text{ }{\scriptscriptstyle 1\!/\!{ }_2}\]

\[=\text{ }64[4\text{ }+\text{ }2\text{ }+\text{ }1\text{ }+\text{ }{\scriptscriptstyle 1\!/\!{ }_2}\text{ }+\text{ }1/{{2}^{2}}]\]

Presently, it’s seen that

\[4,\text{ }2,\text{ }1,~{\scriptscriptstyle 1\!/\!{ }_2},\text{ }1/{{2}^{2}}~is\text{ }a\text{ }G.P.\]

With initial term, \[a\text{ }=\text{ }4\]

Normal proportion, \[r\text{ }=1/2\]

We know,

Accordingly, the necessary aggregate\[=~64\left( 31/4 \right)\text{ }=\text{ }\left( 16 \right)\left( 31 \right)\text{ }=\text{ }496\]