Speed Count With Tens Grouping

How fast can you add up the following numbers list:

8, 3, 6, 1, 9, 7, 5, 0, 5, 2, 4, 8 = ? 

Adding each number one by one is slow and cumbersome. But there are simple methods for improving counting skills; one of which is 'tens grouping'. 

Start by scanning the numbers above. Stop in the sequence whenever you pass a ten. So, the first two numbers are 8 and 3. These together make more than 10. One more than 10, in fact. Remember the '1' (1 more than 10). Then, we need to move another 3 digits into the sequence before the following numbers exceed another ten: 6, 1, 9 makes 6 more than another ten. Add the 6 to the 1, and remember 7. The next two numbers make another ten (7+5) with 2 left over. Add 2 to our 7, and remember 9. We have to go through the next four numbers before we again break another ten (0, 5, 2, 4). This makes one over ten, so we add 1 to our 9 to create 10. We have passed 10 four times, and collected together 10 1's to make 50. Now we just add the last number in the sequence, 8, for '58'.

For lots more advice and strategies for learning and improving your math skills, visit the Optimnem Math page at http://www.optimnem.co.uk/Maths.htm