1. 用简便方法计算下面各题。
$\frac{11}{23}×13 + \frac{13}{23}×12$
$\frac{4}{7}×\frac{13}{11} - \frac{2}{7}×\frac{4}{11}$
$24×\frac{7}{43} + 12×\frac{14}{43}$
$\frac{17}{59}×\frac{12}{63} + \frac{17}{63}×\frac{51}{59}$
$\frac{4}{15}×\frac{18}{25} - \frac{9}{25}×\frac{2}{5}$
$42×\frac{14}{99} +14×\frac{31}{99} +52×\frac{7}{99}$

1. 13
2. $\frac{4}{7}$
3. $\frac{336}{43}$
4. $\frac{17}{59}$
5. $\frac{6}{125}$
6. 14

2. 用简便方法计算下面各题。
$99×\frac{7}{25}+\frac{7}{25}$
$87×\frac{3}{86}$
$11\frac{5}{57}×3$
$\frac{4}{25}×101-\frac{4}{25}$
$2026×\frac{2025}{2027}$
$\frac{9}{55}×61-7×\frac{9}{55}+\frac{9}{55}$
$99\frac{1}{97}×\frac{97}{98}$
$37×\frac{3}{4}+\frac{3}{4}×62+\frac{3}{4}$
$\frac{5}{9}×\frac{5}{8}+\frac{13}{9}×0.625-\frac{5}{8}$

1. 28
2. $3\frac{3}{86}$
3. $33\frac{5}{19}$
4. 16
5. $2024\frac{2}{2027}$
6. 9
7. 98
8. 75
9. $\frac{5}{8}$