yes. 1+ 100= 101 2+99=101 3+98=101 4+97=101 5+96=101 and so on. then its 101 times 50= 5050
100
5050
It's 2550
102*25=2550
5050 To add all numbers from 1 to n: (n/2)(n + 1), in this case n = 100 so it is 50 x 101...
you add all the numbers and divide by how many numbers there are by the answer you get when tou add all the numbers
100
5050
Add up all the numbers, divide the total by how many numbers there were. that is the formula for mean.
It's 2550
-99
The sum is 2500.
All you do is add all of the numbers 3 times and 1 an 9 4 times
If you can count from 1 to 100, then you can name them all. (And in numerical order, I might add.)
5050, ie (1 + 100) x (100/2)
You could add them up one by one (a spreadsheet will help with this). Or you can use the formula for the sum of an arithmetic series. -------------------------------------- Answer = 101/2 (0 + 100) = 101 x 50 = 5050
You can either just add them up or use quick logic to add them in pairs: All the numbers from 1 to 49 match up with 51 through 99 to = 49 pairs of 100 = 4900, than add the two you skipped 4900 + 50 + 100 = 5050 total