There are 12 even numbers between 2 and 24 inclusive.
The sum is 154.
155
The sum of the first n odd numbers is n squared. 25 x 25 = 625
The sum of the even numbers is (26 + 28 + ... + 100); The sum of the odd numbers is (25 + 27 + ... + 99) Their difference is: (26 + 28 + ... + 100) - (25 + 27 + ... + 99) = (26 - 25) + (28 - 27) + ... + (100 - 99) = 1 + 1 + ... + 1 There are (100 - 26) ÷ 2 + 1 = 38 terms above which are all 1; their sum is 38 x 1 = 38. So the difference of the sum of all even numbers and all odd numbers 25-100 is 38.
25 of them
There is no solution. You could do it if the numbers were odd: 25 and 27 are consecutive odd numbers that equal 52.
The sum of the first 25 prime numbers is 1,060.
155
Oh honey, you're really asking me to add up the first 25 even numbers? Bless your heart. Well, technically speaking, the sum of the first 25 even numbers is 650. So there you have it, darling. Math can be a real hoot sometimes.
The sum of the first 25 prime numbers is 1,060.
The sum of the first 25 numbers is 25*26/2 = 325 So the sum of the first 25 multiples of 12 is 325*12 = 3900
Oh, what a happy little question! Let's take a look at those prime numbers. When we add them up, we find that their sum is actually even. Isn't that just a delightful surprise? Remember, in the world of numbers, there's always a little bit of magic waiting to be discovered.
625
The sum of the first n odd numbers is n squared. 25 x 25 = 625
The sum of the even numbers is (26 + 28 + ... + 100); The sum of the odd numbers is (25 + 27 + ... + 99) Their difference is: (26 + 28 + ... + 100) - (25 + 27 + ... + 99) = (26 - 25) + (28 - 27) + ... + (100 - 99) = 1 + 1 + ... + 1 There are (100 - 26) ÷ 2 + 1 = 38 terms above which are all 1; their sum is 38 x 1 = 38. So the difference of the sum of all even numbers and all odd numbers 25-100 is 38.
By using the formula for an arithmetic series. This is basically obtained by reasoning: The sum of the first 25 numbers is the same as 25 multiplied by the average of those numbers; the average in this case is simply (1 + 25) / 2.
25 of them
If the sum of 2 numbers is 25 and their product is 156, the 2 numbers would be 12 and 13.