网址：http://m.1010jiajiao.com/timu3_id_578994[举报]
算一算．
20连续加7，写出每次加得的和．
20，27________，________，________，________，________，________．
80
80 72 ____ ____ ____ ____ ____ ____ ____
60连续减5，写出每次减得的差．
60：55 ________ ________ ________ ________ ________
90连续减9，写出每次减得的差．
90：81 ________ ________ ________ ________ ________