Question

here are some numbers 10 13 15 20 27 39.
10 15 20 is an arithmetic progression
describe the rule

Answer 1

Answer:

$a_{n}$ = 5n + 5

Step-by-step explanation:

The nth term of an arithmetic progression is

$a_{n}$ = a₁ + (n - 1)d

where a₁ is the first term and d the common difference

Here a₁ = 10 and d = a₂ - a₁ = 15 - 10 = 5 , then

$a_{n}$ = 10 + 5(n - 1) = 10 + 5n - 5 = 5n + 5