I’ve been really enjoying watching my son learn a little bit about percentages lately. What’s been particularly interesting to me is the difference in his mind between fractions, decimals and percents. It will be fun to see the moment(s) when these ideas all connect in his mind.
Today we looked at a problem based on one of the review problems from our Prealgebra book. First we walked through a solution where he set to ratios equal to each other:
Next I asked him to show his original approach to the problem which is a little more intuitive and less procedural than the above solution. When he finished showing this alternate solution, I showed him that – surprise – both solutions are really the same!
Mike's Math Page 