In an arithmetic progression, it is known that a1 = 3, d = -2. find the third term of the progression.

Let’s use the formula to find any member of an arithmetic progression, knowing its first term and the difference of this progression:

аn = a1 + d * (n – 1),

Where:

a1 – the first member of the arithmetic progression,

d – difference of arithmetic progression,

n is the ordinal number of a member of the progression.

We calculate the third term of this arithmetic progression:

a3 = a1 + d * (3 – 1),

a3 = 3 + (-2) * 2 = 3 – 4 = -1.

Answer: a3 = -1.