Week 1 – Arithmetic Sequences

32, 39, 46, 53, 60… d= 7

Part One:

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

$t_{50}= 32 + (49)7$

$t_{50}= 32 + 343$

$t_{50}= 375$

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

$t_n= 32 + (n-1)7$

$t_n= 32 + 7n - 7$

$t_n= 25 + 7n$

Part Two:

$S_n= \frac{n}{2} (t_1 + t_n)$

$S_{50}= \frac{50}{2} (32 + 50)$

$S_{50}= 25 (82)$

$S_{50}= 2050$

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