How to Add 5 Consecutive Numbers Quickly

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To add 5 consecutive numbers quickly, you can use the formula for the sum of an arithmetic series:

sum = (n/2) x (first number + last number)

where n is the number of terms in the series, and the first and last numbers are the first and last terms in the series.

So, to add 5 consecutive numbers quickly, you can simply use this formula by plugging in the values:

sum = (5/2) x (first number + last number)

Since we are adding 5 consecutive numbers, the first and last numbers are consecutive integers, which means that the last number is equal to the first number plus 4.

Therefore, we can rewrite the formula as:

sum = (5/2) x (first number + (first number + 4))

Simplifying the formula:

sum = (5/2) x (2 x first number + 4)

sum = 5 x (first number + 2)

So, to add 5 consecutive numbers quickly, you can add the first number to 2, multiply the result by 5, and you will have the sum of the 5 consecutive numbers.