一次智力竞赛,老师出了33道题,规定答对一道题得8分,答错一道扣3分,小红全部答了,结果得了0分,小红答对了 道题.
÷15=0.8==16: = %= 折.
0.8==12÷ = 折= %
3÷ == :12=七成五= %
=0.75=15÷ .
9: == ÷32== :56.