人教版小学数学三年级下册口算练习题

数学三年级（下册）口算练习题400X7 = 80X9 = 400X8 = 440X8 = 80X6 = 300X5 = 600X7 = 6X300 = 90X7 = 80X6= 600X8 = 50X