《2025年天天练口算六年级数学上册人教版》

$(\frac{1}{7}+\frac{1}{4})× 28$
$=\frac{1}{7}× 28+\frac{1}{4}× 28$
$=$$4 + 7$
$=$$11$
$\frac{1}{9}× \frac{7}{10}× \frac{25}{14}$
$=\frac{1}{9}× (\frac{7}{10}× \frac{25}{14})$
$=$$\frac{1}{9}× \frac{5}{4}$
$=$$\frac{5}{36}$
$56× \frac{3}{55}$
$=$$(55 + 1)×\frac{3}{55}$
$=$$55×\frac{3}{55} + 1×\frac{3}{55}$
$=$$3 + \frac{3}{55}$
$36× (\frac{1}{4}+\frac{2}{9})$
$=$$36×\frac{1}{4} + 36×\frac{2}{9}$
$=$$9 + 8$
$=$$17$

答案： $(\frac{1}{7}+\frac{1}{4})× 28$
$=\frac{1}{7}× 28+\frac{1}{4}× 28$
$=4 + 7$
$=11$
$\frac{1}{9}× \frac{7}{10}× \frac{25}{14}$
$=\frac{1}{9}× (\frac{7}{10}× \frac{25}{14})$
$=\frac{1}{9}× \frac{5}{4}$
$=\frac{5}{36}$
$56× \frac{3}{55}$
$=(55 + 1)×\frac{3}{55}$
$=55×\frac{3}{55} + 1×\frac{3}{55}$
$=3 + \frac{3}{55}$
$=3\frac{3}{55}$
$36× (\frac{1}{4}+\frac{2}{9})$
$=36×\frac{1}{4} + 36×\frac{2}{9}$
$=9 + 8$
$=17$

$32× \frac{3}{4}=$24
$\frac{2}{5}× 30=$12
$\frac{2}{9}× 3.6=$0.8
$\frac{5}{8}× \frac{8}{5}=$1
$\frac{5}{6}+\frac{2}{6}=$$\frac{7}{6}$
$1-\frac{3}{4}=$$\frac{1}{4}$
$\frac{4}{9}+\frac{1}{3}=$$\frac{7}{9}$
$21+\frac{3}{5}=$$21\frac{3}{5}$
$\frac{1}{5}+\frac{1}{6}=$$\frac{11}{30}$
$80× \frac{3}{4}=$60
$\frac{5}{6}× \frac{2}{5}=$$\frac{1}{3}$
$\frac{7}{15}× 4.5=$2.1
$\frac{11}{12}+\frac{1}{12}=$1
$8.1× \frac{2}{9}=$1.8
$50× \frac{1}{2}=$25

答案： 解析：
这些题目都是基础的数学运算，包括分数乘法、加法、减法和与小数的混合运算。我们需要运用基本的算术规则和分数运算规则来解决这些问题。
答案：
$32 × \frac{3}{4} = 24$
$\frac{2}{5} × 30 = 12$
$\frac{2}{9} × 3.6 = 0.8$
$\frac{5}{8} × \frac{8}{5} = 1$
$\frac{5}{6} + \frac{2}{6} = \frac{7}{6}$
$1 - \frac{3}{4} = \frac{1}{4}$
$\frac{4}{9} + \frac{1}{3} = \frac{7}{9}$
$21 + \frac{3}{5} = 21\frac{3}{5}$ 或者 $21.6$
$\frac{1}{5} + \frac{1}{6} = \frac{11}{30}$
$80 × \frac{3}{4} = 60$
$\frac{5}{6} × \frac{2}{5} = \frac{1}{3}$
$\frac{7}{15} × 4.5 = 2.1$
$\frac{11}{12} + \frac{1}{12} = 1$
$8.1 × \frac{2}{9} = 1.8$
$50 × \frac{1}{2} = 25$