How do you find three consecutive odd integers?

1 Answer
Jun 10, 2015

Three consecutive odd integers are always of the form (2k+1), (2k+3) and (2k+5) for some integer k.

Explanation:

Every odd integer can be expressed in the form 2k+1 for some integer k.

Given an odd integer 2k+1, the next odd integer is (2k+1)+2 = 2k+3 and the next after that is 2k+5.

If you want to find three consecutive odd integers to satisfy some property then you can substitute these expressions into the condition and solve for k.

For example, to find three consecutive odd integers whose sum is 189 you can write:

189 = (2k+1) + (2k+3) + (2k+5) = 6k+9

Subtract 9 from both sides to get:

180 = 6k

Divide both sides by 6 to get k = 30.

Then our three odd integers are

(2k + 1) = 61, (2k+3) = 63 and (2k+5) = 65