Answer:
The value for 20th term is 10.
Step-by-step explanation:
First, you have to find the formula for the sequence.
[tex]an = a + d(n - 1)[/tex]
[tex]let \: a = 200,d = - 10[/tex]
[tex]an = 200 - 10(n - 1)[/tex]
[tex]an = 200 - 10n + 10[/tex]
[tex]an = - 10n + 210[/tex]
Given that the formula of this sequence is an = -10n + 210. Next, you have to find 20th term :
[tex]let \:n = 20[/tex]
[tex]20th \: term = - 10(20) + 210[/tex]
[tex]20th \: term = - 200 + 210[/tex]
[tex]20th \: term = 10[/tex]
(Correct me if I am wrong)