69÷(3+23)=69÷3+69÷23 .(判断对错)
0.75== ÷16=27: = %.
= : =33÷ = %
÷4=25%= : =8÷ = 折.
0.75= : = :25= 折= %= (成数)
10: ==0.625=5÷ = %