口袋里有同样大小的8个白球、5个黄球和l5个黑球.闭上眼睛从口袋中摸球,至少取出多少个球,才能保证摸出的这几个球中有黑球?
直接写出得数.= = = == = = == = = == = = == = = == = = ==
直接填得数×= ×= 16×= ÷= 1÷=÷= 9÷= ÷33= 1﹣25%= 75%+0.25=÷= ﹣=
直接写出得数. =80%= 1÷10%= 74×4×25%= ×15%=
直接写出得数×24= ÷= 25××= 5.8×9+5.8=+= 5÷5÷= ÷÷×= 1÷2.5%=
直接写得数.×= ÷= 1﹣=0.13= (+)×8= ﹣=+= ×= 0÷=÷3×÷3=