1.Tính
a) (\(\dfrac{-2}{3}\)+1\(\dfrac{1}{4}\)-\(\dfrac{1}{6}\)).\(\dfrac{-24}{10}\)
b) \(\dfrac{13}{15}\).0,25.3+(\(\dfrac{8}{15}\)-\(1\dfrac{19}{60}\)):\(1\dfrac{23}{24}\)
c) (\(\dfrac{12}{32}\)+\(\dfrac{5}{-20}\)-\(\dfrac{10}{24}\)):\(\dfrac{2}{3}\)
d) \(4\dfrac{1}{2}\):(2,5-\(3\dfrac{3}{4}\))+(\(\dfrac{-1}{2}\))\(^2\)
e) \(\dfrac{-5}{2}\):(\(\dfrac{3}{4}\)-\(\dfrac{1}{2}\))
2. Tính nhanh
a) \(\dfrac{5}{23}\).\(\dfrac{17}{26}\)+\(\dfrac{5}{23}\).\(\dfrac{10}{26}\)-\(\dfrac{5}{23}\)
b) \(\dfrac{1}{7}\).\(\dfrac{5}{9}\)+\(\dfrac{5}{9}\).\(\dfrac{2}{7}\)+\(\dfrac{5}{9}\).\(\dfrac{1}{7}\)+\(\dfrac{5}{9}\).\(\dfrac{3}{7}\)