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Digit Sum

What is the sum of all the digits in all the integers from one to one million?

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Legs Eleven

Take any four digit number. Move the first digit to the end and move the rest along. Now add your two numbers. Did you get a multiple of 11?

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Football Sum

Find the values of the nine letters in the sum: FOOT + BALL = GAME

Add to 200

Age 11 to 14 Challenge Level:

Choose any four digits (from 0, 1, 2, ... , 9) and place them in the cells below (you can repeat digits).

 
Read the two 2-digit numbers across and add them together.
Read the two 2-digit numbers down and add them too.
Then add these two totals together.

For example:
             

Try a few examples of your own.

Is there a quick way to tell if the total is going to be even or odd?

Can you make a total of 200? 
How many ways are there of doing this?

If we use four 0s, the total would be 0.
If we use four 9s, the total would be 396.
Which numbers between 0 and 396 is it possible to make?


With thanks to Don Steward, whose ideas formed the basis of this problem.