Hi Marie,

Thanks for your post. Note that in the previous lesson you subtracted directly from the quantity of 10 and looked to see how many beads were remaining on both strings and then added them up to get your answer.

With the Down over ten you're subtracting from the 2nd string and then going over the 10, or another way to say it is continuing to subtract with the 10 after having subtracted all you can from the 2nd string. Another way I suppose you could look at it is Up over ten subtraction since you're going up a string to start subtracting from the 10. Does this help? All this is is a name to give to this strategy to help differentiate the different strategies.

Sincerely, Rosine

Yes it helps. Thanks!