1. 直接写出得数。
实际用时：分钟
$8÷\frac{2}{3}=$
$6÷\frac{2}{5}=$
$8÷\frac{3}{4}=$
$6÷\frac{3}{4}=$
$13÷\frac{13}{14}=$
$16÷\frac{4}{11}=$
$18÷\frac{9}{13}=$
$21÷\frac{7}{23}=$
$5÷\frac{1}{2}=$
$6÷\frac{1}{3}=$
$11÷\frac{11}{2}=$
$4÷\frac{1}{3}=$
$13÷\frac{13}{5}=$
$12÷\frac{3}{4}=$
$10÷\frac{10}{13}=$
$4÷\frac{1}{4}=$
$8÷\frac{5}{6}=$
$4÷\frac{1}{5}=$
$3÷\frac{1}{6}=$
$2÷\frac{3}{4}=$
$5÷\frac{2}{7}=$
$12÷\frac{1}{4}=$
$14÷\frac{7}{12}=$
$12÷\frac{1}{2}=$

1. $12$ $15$ $\frac{32}{3}$ $8$
$14$ $44$ $26$ $69$
$10$ $18$ $2$ $12$
$5$ $16$ $13$ $16$
$\frac{48}{5}$ $20$ $18$ $\frac{8}{3}$
$\frac{35}{2}$ $48$ $24$ $24$

2. 计算下面各题。
$\frac{1}{2}+\frac{1}{4}+\frac{1}{8}$
$\frac{9}{10}-(\frac{1}{5}+\frac{1}{4})$
$\frac{13}{20}+\frac{17}{18}+\frac{7}{20}+\frac{1}{18}$

2. $\frac{7}{8}$ $\frac{9}{20}$ $2$

3. 填一填。
$(\quad)×2=\frac{1}{5}$
$(\quad)×4=\frac{2}{3}$
$\frac{5}{4}×(\quad)=\frac{1}{6}$
$(\quad)÷2=\frac{1}{5}$
$(\quad)÷4=\frac{2}{3}$
$\frac{5}{4}÷(\quad)=\frac{1}{6}$
$15×(\quad)=\frac{3}{5}$
$15÷(\quad)=\frac{3}{5}$
$\frac{5}{9}÷(\quad)=\frac{3}{4}$

3. $\frac{1}{10}$ $\frac{1}{6}$ $\frac{2}{15}$
$\frac{2}{5}$ $\frac{8}{3}$ $\frac{15}{2}$
$\frac{1}{25}$ $25$ $\frac{20}{27}$

对于$a,b:a△ b = a× b - a÷ b$。比如$6△ 2 = 6× 2 - 6÷ 2 = 12 - 3 = 9$。那么$(12△ 4)△ 3$的值是多少？

【思维提升】120