看图填空:∠1= 度;∠2= 度;∠3= 度;∠4= 度.
3: =12÷ =0.75== %= (折数)
5: =0.25=3÷ == %.
18: ==七五折= %
÷ = :10=0.8== %
÷12=15÷ ==0.25= %