The sum is 1,060
99
The sum of the numbers from 1 through 100 is 5,050.
The sum of the squares of the first 100 natural numbers [1..100] is 338350, while the sum of the first 100 natural numbers squared is 25502500.
If, 100 is included by "between", the answer is 2550. If not, it is 2450.
The sum is 1,060
99
1060
The sum of prime numbers between 1 and 25 is 100. 2 + 3 + 5 + 7 + 11 +13 +17 + 19 + 23 = 100
The sum of the numbers from 1 through 100 is 5,050.
The sum of the squares of the first 100 natural numbers [1..100] is 338350, while the sum of the first 100 natural numbers squared is 25502500.
If, 100 is included by "between", the answer is 2550. If not, it is 2450.
The sum is 2500.
101
The sum of the whole numbers from 1 to 100 inclusive is 5,050.
The sum of these composite numbers, including 100, is 3989.The sum of all numbers between 1 and 100 is 5,050. From this we need to subtract the sum of 1 plus all the prime numbers below 100. The sum of the primes is 1,060. Subtracting (1 + 1060) or 1,061 from 5,050 yields 3,989.
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.