My Arithmetic Sequence

$t_{50}$

$5,10,15,20,25$ …

$t_n$ = $t_1$ + (n-1)(d)

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

$t_{50}$ = 5 + 245

$t_{50}$ = 250

$t_n$

$t_n$ = 5 + (n-1)(5)

$t_n$ = 5 + $5_n$ – 5

Add like terms

$t_n$ = $5_n$

$s_{50}$

$s_{50}$ = $\frac{50}{2}$ ( $t_1$ + $t_{50}$ )

$s_{50}$ = 25 (5 + 250)

$s_{50}$ = 25 (255)

$s_{50}$ = 6375

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