Blog post – Sep 10th

Posted on September 10, 2018 by mollym2016 under Grade 11, Math 11, Pre-calc 11

Arithmetic sequence:

6, 12, 18, 24, 30

1. find $t_{50}$

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

$t_{50} = 6 + 6(50-1)$

$t_{50} = 6 + 300 - 6$

$t_{50} = 300$

2. find $S_{50}$

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

$S_{50} = (6+300)(\frac{50}{2})$

$S_{50} = (306)(25)$

$S_{50} = (306)(25)$

$S_{50} = 7650$