Instead of adding each digit in turn, acknowledge that there are 100 numbers to add, and then multiply that by the average of 1 and 100.
Ie. 100×(1+100)÷2=100×101;÷2
100×101;÷2=50×101=5050
So, in short, the answer is: 5050
25
Many of them.
The integers are -11, -9 and -7.
Add them up. Divide their total by the number of integers there are.
It is 50.
25
Many of them.
100
No two consecutive integers can add up to 98.No three consecutive integers can add up to 98.But 23, 24, 25, and 26 can.
To find the sum of integers in a square grid that match a given value, add up all the matching integers in the grid.
2,500 50 times 50 equals 2,500 50 plus 50 equals 100
5050
The integers are -11, -9 and -7.
Add them up. Divide their total by the number of integers there are.
It is 50.
101+102=203
Because otherwise you would only know how to subtract and add with the same integers. Not a particularly useful skill unless just those integers turned up!