8/19 × 5/11 + 8/19 × 6/11 + 11/19
= 8/19 × (5/11 + 6/11) + 11/19
= 8/19 × 1 + 11/19
= 8/19 + 11/19
= 1
Ủng hộ mk nha ♡_♡
8/19 × 5/11 + 8/19 × 6/11 + 11/19
= 8/19 × (5/11 + 6/11) + 11/19
= 8/19 × 1 + 11/19
= 8/19 + 11/19
= 1
Ủng hộ mk nha ♡_♡
B=\(\frac{5}{7}.\frac{14}{11}-\frac{5}{7}.\frac{5}{11}-\frac{5}{11}.\frac{2}{7}\)
C=\(1+\frac{2}{6}+\frac{2}{12}+\frac{2}{20}+\frac{2}{30}+\frac{2}{42}\)
D=\(\frac{0,75-0,6+\frac{3}{19}+\frac{3}{19}}{2,75-2,2+\frac{11}{19}+\frac{11}{91}}\)
Tính :
a) 3,5 x 2 + 1,25 x 4
b) \(\frac{3}{4}+2\times\left(\frac{1}{2}-\frac{1}{15}\right)\)
c) \(\frac{7}{11}\times\frac{1}{19}+\frac{7}{11}\times\frac{8}{19}-\frac{4}{11}\)
\(\left(19\frac{3}{8}-5\frac{1}{9}\right)-\left(11\frac{3}{8}-3\frac{1}{9}\right)=\)
Tính :
a) 16,88 + 9,76 +3,12 - 5,13
b) \(\frac{11}{19}+\frac{8}{13}+\frac{3}{11}\)
c) \(\frac{1}{2}\div\frac{1}{4}-\frac{1}{6}\)
\(\frac{19}{35}+\frac{15}{19}+\frac{16}{35}+\frac{23}{19}+\frac{4}{15}+\frac{11}{15}\)
Tính giá trị của các biểu thức sau một cách nhanh nhất:
a)0.2x517x7x0.7x483x2
b)\(\frac{4}{9}+\frac{6}{11}+\frac{5}{9}+\frac{16}{11}+7\)
c)\(\frac{3}{5}+\frac{5}{1}+\frac{7}{13}+\frac{2}{5}+\frac{16}{11}+\frac{19}{13}\)
Bài 1:
a, \(\frac{3}{5}\)+ \(\frac{6}{11}\)+\(\frac{7}{13}+\frac{6}{11}\)+\(\frac{2}{5}+\frac{19}{13}\)
b,\(\frac{6}{5}\)x\(\frac{3}{8}+\frac{5}{8}\)x\(\frac{6}{5}-\frac{4}{5}\)
c,4 x 5 x 6 x 7 x 8
________________
8 x 10 x12 x 14x 16
TÍNH
\(\frac{1}{2}+\frac{5}{6}+\frac{11}{12}+\frac{19}{20}+\frac{29}{30}+\frac{41}{42}+\frac{55}{56}\)
Tính nhanh : \(\frac{5}{6}+\frac{11}{12}+\frac{19}{20}+\frac{29}{30}+\frac{41}{42}+\frac{55}{56}+\frac{71}{72}+\frac{89}{90}\)