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Problem 1
$\displaystyle r = 2 ; a = 7$
$\displaystyle T_{n} = ar^{n - 1}$
$\displaystyle T_{10} = (7)(2)^{10 - 1}$
$\displaystyle = (7)(2^9)$
$\displaystyle = 3584$
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Problem 2
$\displaystyle S_{n} = \frac{ a( 1 - r^n ) }{ 1 - r }$
$\displaystyle S_{5} = \frac{ 3( 1 - (-1,5)^5 ) }{ 1 - (-1,5) }$
$\displaystyle S_{5} = \frac{165}{16}$