What is the sum of even numbers from 3 to 18? Here we will show you step-by-step how to calculate the sum of even numbers from 3 to 18.
Step 1) We start by finding the first (F) and last (L) even numbers from 3 to 18. It is easy to do that by simply looking at the numbers. The first even number is 4, and the last even number is 18.
F = 4
L = 18
Step 2) Next, we calculate the total even numbers (T) there are from 3 to 18, using a formula. Here is the formula and the math:
T = (L - F + 2) ÷ 2
T = (18 - 4 + 2) ÷ 2
T = 16 ÷ 2
T = 8
Step 3) Finally, we use the information from Step 1 and Step 2, and another formula, to calculate the sum of even numbers from 3 to 18, like this:
Sum = (T ÷ 2) × (2 × F + (2 × (T - 1))
Sum = (8 ÷ 2) × (2 × 4 + (2 × (8 - 1))
Sum = 4 × (8 + 14)
Sum = 4 × 22
Sum = 88
Sum of even numbers from 3 to 18 = 88
Sum of Even Numbers Calculator
Please use the tool below to calculate the sum of even numbers for another set of numbers.