The Sum of Three Consecutive Even Numbers Is 90: How to Find the Largest Number Simply

Are you curious about how to quickly determine the sum of three consecutive even numbers when you already know their total? Discover an easy method to solve this classic math puzzle—perfect for students, teachers, and anyone interested in numbers.

In this article, we’ll explore how to find the largest of three consecutive even numbers whose total is 90, using simple algebra and logic. We’ll also explain why this approach works and how to apply it in real-life math problems.

Understanding the Context


What Are Consecutive Even Numbers?

Consecutive even numbers are even numbers that follow each other in sequence without gaps. For example: 2, 4, 6 or 10, 12, 14.

An important rule: Every set of three consecutive even numbers can be written as:
n, n + 2, n + 4,
where n is the smallest even number.

Key Insights


Given: The Sum Equals 90

We’re told:
n + (n + 2) + (n + 4) = 90

Let’s simplify this step-by-step:

  1. Add the expressions:
    n + n + 2 + n + 4 = 90
    → 3n + 6 = 90

  2. Solve for n:
    3n = 90 – 6
    3n = 84
    n = 84 ÷ 3
    n = 28

Final Thoughts

So the three numbers are:
28, 30, and 32


Find the Largest Number

From the calculation above, the largest of the three consecutive even numbers is:
n + 4 = 28 + 4 = 32


Quick Verification

28 + 30 + 32 = 90 ✓
The largest number is indeed 32


A Faster Way to Solve Any Such Problem

Since three consecutive even numbers follow a simple arithmetic sequence, once you use the formula for the sum:
Sum = 3n + 6,
you can solve for n, then compute the largest number as:
Largest number = n + 4 = (90 – 6)/3 + 4 = 28 + 4 = 32