Long Division can just "Chunk" off!

Tell me how you would work out this sum?

  • 1386 divided by 6

I know how I'd do it.  I'd write the number six on piece of paper, draw a bracket around it and then a short line stretching out to the right.  Then I'd write 1358 below that line.  I divide 6 into 13 (write 2 above the line, note the remainder 1, carry the one over to the 8 to make 18).  I divide 6 into 18 (exactly 3 - write it above the line).  I divide 6 into 6 (exactly 1 - again, I write it above the line).  Answer?  231.  That was easy, wasn't it?

Picture the scene - child #3 comes home with maths homework and, as you already know, homework is a bone of contention in our house, but I settle down to despair at him and tear my hair out talk him through how to work it out.

I show him the above method of working out long division and he doesn't understand,
"Mum, we don't do it like that.  We do 'chunking'."
"Eh?  What's 'chunking'?"

He draws a long line on the paper, writes 1386 at one end of the line a 0 at the other.  Then he makes "rainbows" of sums and answers, subtracting each answer from 1386 (and subsequent answers) as he goes along, until he reaches zero.  Then he adds up the numbers that he's written in the rainbows.  Fifteen minutes later he arrives at the same answer I've managed to calculate in about 30 seconds.

He tried to explain it to me but my. brain. would. not. compute.  I felt old but was convinced my method was better, faster and used less brain power - winner all round.  Child #3 disagreed and gave me a withering look.  

Chunking is explained here for those who feel they may need to learn about these things - as long as you are young enough to digest the information...

This blog post was written for Workshop #12 - What has made you feel a little old this week? - run by Josie at Sleep Is For The Weak