《折扣和成数》口算练习

$\frac {3} {5}\times \frac {5} {7}\times \frac {2} {3}$=

$\frac {1} {2}\times \frac {1} {3}+\frac {1} {2}\times \frac {2} {3}$=

55%=折

五折=%

8×4×12.5×0.25=

56÷（0.3+2.5）=

$28\times \frac {3} {14}$=

一折=%

$\frac {3} {7}\div 6$=

两折=%

七五折=%

30%=折