How do you find the next four terms of the arithmetic sequence 1.3, 3.8, 6.3, ...?

Question

1900 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2017-01-10T12:59:06

$8.8, 11.3, 13.8, 16.3$ $8.8,11.3,13.8,16.3$

The difference between the n-th term and the (n-1)-th is:

$6.3 - 3.8 = 3.8 - 1.3 = 2.5$ $6.3-3.8=3.8-1.3=2.5$

Then, you can get the next term by adding 2.5:

$a_{1} = 1.3$ $a_1=1.3$
$a_{2} = 3.8$ $a_2=3.8$
$a_{3} = 6.3$ $a_3=6.3$

$a_{4} = 6.3 + 2.5 = 8.8$ $color(red)(a_4=6.3+2.5=8.8)$

$a_{5} = 8.8 + 2.5 = 11.3$ $color(red)(a_5=8.8+2.5=11.3)$

$a_{6} = 11.3 + 2.5 = 13.8$ $color(red)(a_6=11.3+2.5=13.8)$

$a_{7} = 13.8 + 2.5 = 16.3$ $color(red)(a_7=13.8+2.5=16.3)$