What is the sum of even numbers from 21 to 37? Here we will show you step-by-step how to calculate the sum of even numbers from 21 to 37.
Step 1) We start by finding the first (F) and last (L) even numbers from 21 to 37. It is easy to do that by simply looking at the numbers. The first even number is 22, and the last even number is 36.
F = 22
L = 36
Step 2) Next, we calculate the total even numbers (T) there are from 21 to 37, using a formula. Here is the formula and the math:
T = (L - F + 2) ÷ 2
T = (36 - 22 + 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 21 to 37, like this:
Sum = (T ÷ 2) × (2 × F + (2 × (T - 1))
Sum = (8 ÷ 2) × (2 × 22 + (2 × (8 - 1))
Sum = 4 × (44 + 14)
Sum = 4 × 58
Sum = 232
Sum of even numbers from 21 to 37 = 232
Sum of Even Numbers Calculator
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