The sum of the smallest 15 positive integers is 120.
The sum of the smallest 15 negative integers is -120.
The sum of the first five whole numbers is 10.
the sum of the first 15 prime numbers is 328 .
The sum of the first 15 odd numbers is 225.
The sum of the first 5 numbers is 15. 1+2+3+4+5=15
They are 12 and 15
12 and 3.
7 and 8
The sum of the first 15 positive even numbers is 240. (Simply square 15, then add 15 to the result: 15 x 15 = 225. 225 + 15 = 240).
15 and 5
It is 15*(1 + 2)
7 and 8. You know that the sum of any two consecutive whole numbers, x and x +1, is 2x +1 2x + 1 = 15 2x = 14 x = 7
(1+15)*15/2first plus last times number of numbers then divide by two