1.Thực hiện phép tính:
a) 45 : 2frac{4}{7}+50o/o - 1,25
b) 4frac{2}{5}.0,5-1frac{3}{7}.14o/o + (-0,8)
c) 1frac{3}{8}+frac{1}{8}:(75o/o - frac{1}{2}) - 25o/o . frac{1}{2}
d) 75o/o + 18 + 1,25 . frac{4}{5}-18frac{3}{4}
2.THPT:
A frac{9}{1.2}+frac{9}{2.3}+frac{9}{3.4}+...+frac{9}{98.99}+frac{9}{99.100}
B frac{2}{5.7}+frac{2}{7.9}+frac{2}{9.11}+...+frac{2}{93.95}
C left(1-frac{1000}{2017}right).left(1-frac{1001}{2017}right)...left(1-frac{2017}{2018}right)
D frac{5}{2.7}+frac{4}{7.11}+fr...
Đọc tiếp
1.Thực hiện phép tính:
a) 45 : \(2\frac{4}{7}+50\)o/o - 1,25
b) \(4\frac{2}{5}.0,5-1\frac{3}{7}.14\)o/o + (-0,8)
c) \(1\frac{3}{8}+\frac{1}{8}:\)(75o/o - \(\frac{1}{2}\)) - 25o/o . \(\frac{1}{2}\)
d) 75o/o + 18 + 1,25 . \(\frac{4}{5}-18\frac{3}{4}\)
2.THPT:
A = \(\frac{9}{1.2}+\frac{9}{2.3}+\frac{9}{3.4}+...+\frac{9}{98.99}+\frac{9}{99.100}\)
B = \(\frac{2}{5.7}+\frac{2}{7.9}+\frac{2}{9.11}+...+\frac{2}{93.95}\)
C = \(\left(1-\frac{1000}{2017}\right).\left(1-\frac{1001}{2017}\right)...\left(1-\frac{2017}{2018}\right)\)
D = \(\frac{5}{2.7}+\frac{4}{7.11}+\frac{3}{11.14}+\frac{1}{14.15}+\frac{13}{15.28}\)
3. Tìm x:
a)\(\left(2\frac{4}{5}x-50\right):\frac{2}{3}=51\)
b) \(3\frac{1}{3}x+16\frac{3}{4}=-13,25\)
c) \(\frac{2}{3}x-\frac{5}{6}x=\frac{11}{24}\)
d) x + \(\frac{2}{5}x=\frac{-14}{55}\)
e) \(\frac{2}{5}x-x=\frac{\left(-2018\right)^0}{5^2}\)
f) x + \(\left(x+\frac{2}{7}\right)+\frac{-5}{11}=\frac{4}{11}\)
Help me!!!!!!