两位数乘两位数的笔算不进位(练习讲评)

http://www.zxyq.com.cn/zxyqh5/public/study_sp.php?bkid=4fea69aa379a7&bmid=4fea7179d030f&psid=6&vid=54c350f2b1a6d&isCharge=1&sv=1&gradecode=3&termcode=2&pbmid=4fea7164379a7 两位数乘两位数的笔算不进位(练习讲评)