Arithmetic sequences

5,10,15,20,25

common d= 5

$t_{50}= 5+{(50-1)}{(5)}$

$t_{50}= 5+{(49)}{(5)}$
$t_{50}=5+245$
$t_{50}=249$

$tn= 5+(n-1) 5$ $t_{n}= 5+{(49n)}{-5}$ $t_{n}= -245n-5$

$S_{50}=\frac{50}{2}{(5+250)}$
$S_{50}={25}{(255)}$
$S_{50}={6375}$

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