What is the 20th term of the linear sequence?1,7,13,19,25
1 answer:
Answer:
115
Step-by-step explanation:
There is a common difference d between consecutive terms, that is
d = 7 - 1 = 13 - 7 = 19 - 13 = 25 - 19 = 6
This indicates the sequence is arithmetic with n th term
= a₁ + (n - 1)d
where a₁ is the first term and d the common difference
Here a₁ = 1 and d = 6 , thus
a₂₀ = 1 + (19 × 6) = 1 + 114 = 115
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