Monday, December 9, 2013

Singapore Math--Model Drawing vs. Algebra

I was lucky enough to watch Kim Bell present at NCCTM a bit ago.  Kim is another wonderful SDE presenter.  She showed this wonderful comparison of model drawing to algebra.  I'm using this here with her permission.

Mrs. Grant made 300 cookies. She sold  3/4  of them and gave  1/3  of the remainder to her neighbor. How many cookies were left?

¾ * (y )+ 1/3 (1/4 * y) + x= y
Let y=300 (total cookies)
¾ * 300 + 1/3 (1/4 * 300) + x=300
225 + 1/3 (1/4*300) + x=300
225 + 1/3 (75) + x=300
225 + 25 + x=300
250+x=300
250-250 + x=300 – 250
x=50

Watch to video to see how much easier it is with model drawing!!

No comments: