一棵树苗16元,买3棵送1棵。一次买3棵,每棵便宜多少钱?
直接写出得数.= = = = == = = = =
直接写出得数:2.4×= ; = ; :0.75= ; ÷ =0.1;0.180%×= ; 32÷(1+60%)= ; 2﹣1= ; ×40=.
= = = == = = =
直接写得数.÷3= 10÷= ÷= ×=÷= ×= 4×= 1﹣=×60= ×= ×= ××=÷5= 30÷= ÷= ×÷=
直接写出得数.16×= ×= ×= ÷=÷= 9÷= ××=