Bài 1: Tính bằng cách hợp lí: a, \(11\frac{1}{4}-\left(2\frac{5}{7}+5\frac{1}{4}\right)\)b, \(\left(8\frac{5}{11}+3\frac{5}{8}\right)-3\frac{5}{11}\)c, \(-\frac{1}{4}.13\frac{9}{11}-0,25.6\frac{2}{11}\)d, \(\frac{4}{9}:\left(-\frac{1}{7}\right)+6\frac{5}{9}:\left(-\frac{1}{7}\right)\)Bài 2: Tính bằng cách hợp lí( nếu...
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Bài 1: Tính bằng cách hợp lí:
a, \(11\frac{1}{4}-\left(2\frac{5}{7}+5\frac{1}{4}\right)\)
b, \(\left(8\frac{5}{11}+3\frac{5}{8}\right)-3\frac{5}{11}\)
c, \(-\frac{1}{4}.13\frac{9}{11}-0,25.6\frac{2}{11}\)
d, \(\frac{4}{9}:\left(-\frac{1}{7}\right)+6\frac{5}{9}:\left(-\frac{1}{7}\right)\)
Bài 2: Tính bằng cách hợp lí( nếu có)
a,\(\left(1,11+0,19-26\right):\left(2,06+0,54\right)-\left(\frac{1}{2}+\frac{1}{3}\right):2\)
b, \(\left(2\frac{1}{3}+3,5\right):\left(-4\frac{1}{6}+3\frac{1}{7}\right)+7,5\)
c, \(-15,5.20,8+3,5.9,2-15,5.9,2+3,5.20,8\)
Bài 3: Tìm x, biết:
a, \(\frac{2}{7}+x=20,75\)
b, \(-4\frac{1}{5}-x=2,25\)
c, \(x:8,5=2,2\)
d, \(\left(\frac{2x}{5}-1\right):\left(-5\right)=\frac{1}{7}\)
a) 11 1/4- 2 5/7 - 5 1/4
11 1/4 - 5 1/4 - 2 5/7
( 11 -5) + ( 1/4 -1/4) -2 5/7
6 +0 -2 5/7
6- 2 5/7
5+1 - 2 5/7
( 5-2) + ( 1-5/7)
3+( 7/7 -5/7)
3 + 2/7
3 2/7
3+