Câu 2: Tính ( theo BT của mình là các câu ko theo thứ tự nha )
i) 3\(\dfrac{1}{5}\) + 2\(\dfrac{2}{3}\) ;
k) 3\(\dfrac{1}{2}\) - 1\(\dfrac{2}{5}\) ;
l) 5\(\dfrac{1}{2}\). 3\(\dfrac{3}{4}\) ;
x) \(\dfrac{6}{11}\)-\(\dfrac{4}{11}\). \(\dfrac{22}{8}\) ;
m) 6\(\dfrac{1}{3}\):4\(\dfrac{2}{9}\) ;
r) (\(\dfrac{5}{7}\)-\(\dfrac{1}{2}\)) : \(\dfrac{3}{5}\)
s) \(\dfrac{6}{7}\) + \(\dfrac{4}{7}\). \(\dfrac{7}{8}\)
=> GIúp mình nhanh nha - ai đúng; nhanh; trình bày đẹp thì mình TICK !
i. \(3\dfrac{1}{5}+2\dfrac{2}{3}\) = \(\dfrac{16}{5}+\dfrac{8}{3}\) = \(\dfrac{88}{15}\)
k. \(3\dfrac{1}{2}+2\) = \(5\dfrac{1}{2}=\dfrac{11}{2}\)
l.\(5\dfrac{1}{2}.3\dfrac{3}{4}\) = \(\dfrac{11}{2}.\dfrac{15}{4}\) = \(\dfrac{165}{8}\)
x. \(\dfrac{6}{11}-\dfrac{4}{11}.\dfrac{22}{8}\) = \(\dfrac{6}{11}-1=\dfrac{-5}{11}\)
m. \(6\dfrac{1}{3}:4\dfrac{2}{9}=\dfrac{19}{3}:\dfrac{38}{9}=\dfrac{3}{2}\)
r.\(\left(\dfrac{5}{7}-\dfrac{1}{2}\right):\dfrac{3}{5}\) = \(\dfrac{3}{14}:\dfrac{3}{5}=\dfrac{5}{14}\)
s. \(\dfrac{6}{7}+\dfrac{4}{7}.\dfrac{7}{8}=\dfrac{6}{7}+\dfrac{1}{2}=\dfrac{19}{14}\)