\(\dfrac{15}{14}\) : \(\dfrac{10}{21}\) x \(\dfrac{1}{5}\)
\(5\) x \(\dfrac{1}{5}\) + \(\dfrac{1}{5}\)
\(7\) : \(\dfrac{1}{5}\) - \(\dfrac{1}{5}\)
\(6\) + \(\dfrac{1}{5}\) : \(2\)
\(8\) - \(\dfrac{1}{5}\) x \(7\)
3\(\dfrac{1}{3}\)+\(\dfrac{5}{6}\) 4\(\dfrac{5}{7}\)-2\(\dfrac{11}{21}\) 3\(\dfrac{1}{4}\)x\(\dfrac{2}{5}\) 4\(\dfrac{7}{8}\):\(\dfrac{1}{4}\)
tính nhanh
\(\dfrac{1}{3}\) + \(\dfrac{1}{7}\) +\(\dfrac{1}{5}\) +\(\dfrac{32}{40}\) +\(\dfrac{48}{56}\) +\(\dfrac{14}{21}\)
giúp mình với nhé
\(\dfrac{21}{24}\)x\(\dfrac{2}{11}\):\(\dfrac{9}{8}\)=.......
\(\dfrac{17}{9}\)x\(\dfrac{5}{6}\):\(\dfrac{12}{13}\)=.......
So sánh các phân số:
a,\(\dfrac{1}{5}và\dfrac{3}{5}\) b\(\dfrac{8}{21}và\dfrac{8}{9}\) c,\(\dfrac{3}{5}và1\) d,\(\dfrac{7}{5}và1\)
B=\(\dfrac{1}{6}\)+\(\dfrac{1}{15}\)+\(\dfrac{1}{21}\)+\(\dfrac{1}{28}\)+\(\dfrac{1}{36}\)+\(\dfrac{1}{45}\)+\(\dfrac{1}{55}\)+\(\dfrac{1}{66}\)
1 bánh xe quay đc 63 vòng trong 1 phút .Bánh xe đó quay 1344 vòng trong khoảng thời gian bao lâu
A.21 \(\dfrac{2}{7}\) phút B.21\(\dfrac{1}{3}\) phút C.21\(\dfrac{2}{3}\) phút D.22\(\dfrac{5}{21}\)
\(\dfrac{y}{2022}-\dfrac{1}{10}-\dfrac{1}{15}-\dfrac{1}{21}-...-\dfrac{1}{120}=\dfrac{5}{8}\)
Tính nhanh
a, S= \(\dfrac{1}{3}\) + \(\dfrac{1}{15}\) + \(\dfrac{1}{35}\) + \(\dfrac{1}{63}\) + \(\dfrac{1}{99}\) + \(\dfrac{1}{143}\)
b, A = \(\dfrac{1}{3}\) + \(\dfrac{1}{6}\) + \(\dfrac{1}{10}\) + \(\dfrac{1}{15}\) + \(\dfrac{1}{21}\) + \(\dfrac{1}{28}\)
c, H =\(\dfrac{4047991-2010x2009}{4050000-2011x2009}\)
d, T = \(\dfrac{2009x20010+2000}{2011x2010-2020}\)
e, P = \(\dfrac{7589-80,5x69,3}{7485,05-79x69,3}\)
f, B = 5,1 x 42,2 + 1,7 x 448 x 3 - 0,15 x 700
Giúp mình với