\(\dfrac{5}{7} *\dfrac{-4}{19}-\dfrac{5*2}{7}*\dfrac{15}{19*2} =\dfrac{5}{7}*(\dfrac{-4}{19}-\dfrac{15}{19}) =\dfrac{5}{7}*(\dfrac{-19}{19})=\dfrac{-5}{7}\)
BT1: Tính
1) \(\dfrac{7}{80}:\dfrac{\left(-7\right)}{4}-\dfrac{2}{9}:\left(8-\dfrac{8}{3}\right)-\dfrac{\left(-5\right)}{24}.\left(\dfrac{\left(-10\right)}{3}+\dfrac{38}{15}\right)^2\)
2) 1500 - {5\(^3\) . 2\(^3\)- 11 . [ 7\(^2\) - 5. 2\(^3\) + 8 ( 11\(^2\) - 121)]}
BT1: Tìm x, biết
2)\(2+\dfrac{5}{7}+\left(\dfrac{\dfrac{3}{19}+\dfrac{3}{23}-\dfrac{3}{28}}{\dfrac{5}{19}+\dfrac{5}{23}-\dfrac{5}{28}}\right).x=\dfrac{20}{7}\)
BT1: Tìm x, biết
1) \(\dfrac{-2}{5}+\dfrac{5}{3}.\left(\dfrac{3}{2}-\dfrac{4}{15}x\right)=\dfrac{-7}{6}\)
BT1: Tìm x, biết:
7) \(\dfrac{1}{6}.x+\dfrac{1}{10}.x-\dfrac{4}{15}.x+1=0\)
Tính:
1) ( 2\(\dfrac{3}{17}\) - 2\(\dfrac{3}{5}\) ) + ( -2\(\dfrac{3}{17}\) - 1\(\dfrac{2}{5}\) )
2) ( 2\(\dfrac{7}{15}\) - 3\(\dfrac{3}{7}\) ) - ( -\(\dfrac{9}{21}\) + 3\(\dfrac{7}{15}\) )
3) ( 2\(\dfrac{7}{19}\) + 5\(\dfrac{3}{7}\) ) + (-\(\dfrac{14}{38}\) + 1\(\dfrac{4}{7}\) )
Giúp mình nhé!!!!
Tính nhanh
\(4\dfrac{8}{15}-5\dfrac{7}{12}-0\dfrac{1}{15}\)
Tính
\(\dfrac{-3}{5}-\dfrac{4}{5}\cdot\dfrac{10}{3}\)
BT3: Tính nhanh:
1) \(\dfrac{5}{18}+\dfrac{4}{7}+\dfrac{13}{18}+\dfrac{3}{7}\)
2) \(\dfrac{4}{9}.\dfrac{5}{19}.\dfrac{9}{4}\)
tính
a,\((15.\dfrac{3}{5}-19\dfrac{7}{9})-(13\dfrac{3}{5}-17\dfrac{7}{9})\)
b,\([\dfrac{6}{5}-(\dfrac{3}{7}-2\dfrac{1}{7})\div\dfrac{4}{7}].(-\dfrac{3}{5})+\dfrac{2}{3}\div(-\dfrac{5}{6})\)
giúp mình nhé
tính hợp lý giá trị các biểu thức sau :
B= 71\(\dfrac{38}{45}\) - ( 43\(\dfrac{8}{45}\) - 1\(\dfrac{17}{57}\) )
D= ( 19\(\dfrac{5}{8}\) : \(\dfrac{7}{12}\) - 13\(\dfrac{1}{4}\) : \(\dfrac{7}{12}\) ) . \(\dfrac{4}{5}\)
F= ( 9,75 . 21\(\dfrac{3}{7}\) + \(\dfrac{39}{4}\) . 18\(\dfrac{4}{7}\) ). \(\dfrac{15}{78}\)
