What is the sum of odd numbers from 2 to 71? Here we will show you step-by-step how to calculate the sum of odd numbers from 2 to 71.
Step 1) We start by finding the first (F) and last (L) odd numbers from 2 to 71. It is easy to do that by simply looking at the numbers. The first odd number is 3, and the last odd number is 71.
F = 3
L = 71
Step 2) Next, we calculate the total odd numbers (T) there are from 2 to 71, using a formula. Here is the formula and the math:
T = (L - F + 2) ÷ 2
T = (71 - 3 + 2) ÷ 2
T = 70 ÷ 2
T = 35
Step 3) Finally, we use the information from Step 1 and Step 2, and another formula, to calculate the sum of odd numbers from 2 to 71, like this:
Sum = (T ÷ 2) × (2 × F + (2 × (T - 1))
Sum = (35 ÷ 2) × (2 × 3 + (2 × (35 - 1))
Sum = 17.5 × (6 + 68)
Sum = 17.5 × 74
Sum = 1295
Sum of odd numbers from 2 to 71 = 1295
Sum of Odd Numbers Calculator
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