"kristofer, he's working on systems of equations and subtracting fractions?" clearly, even after working with the system for almost five months, it still has the ability to surprise her. a look at the data shows that the students seem to advance in spurts: a kid will grind away at a ...
Khan Academy 数学视频1(for Michel) 立即播放 视频列表 默认排列03:51 122.estimation with decimals小数化简和加法 上传者:lfcacademy 02:15 123.comparing decimals小数比较 上传者:lfcacademy 02:09 124.adding decimals小数加法 上传者:lfcacademy 01:15 125.subtracting decimals小数减法 上传者:lfcacademy...