Posted by Anonymous on Tuesday, November 15, 2011 at 8:19pm.
how to do arrays and expanded algorithms for multiplication example 17x 23 this is for a fourth grader help

math  MathMate, Tuesday, November 15, 2011 at 8:46pm
17*23 can be done in the head as 20²3²=4009=391.
For information on expanded algorithm for teachers, see:
http://mathed.com/NO/NO_2_4_reading.htm