\(-\dfrac{1}{21}+\dfrac{-1}{28}=-\dfrac{1}{12}\)
Chúc bạn học tốt!!!
\(\dfrac{-1}{21}\) + \(\dfrac{-1}{28}\) = \(\dfrac{-4+\left(-3\right)}{84}\) = \(\dfrac{-7}{84}\) = \(\dfrac{-1}{12}\)
-1 phần 21 + -1 phần 28
1. Thực hiện phép tính:
a. 3/4 + -1/8 b. -5/12 + -7/24 c. 4/21 - -5/28 d 1 + -7/28 e. -4/3 - 17/6 f. 1/3 - ( 1/2 +1/8 )
g. 1/21 - ( 1/7 - 1/3 ) h. 1/2 - 1/4 + 1/13 + 1/8
2. Tìm x
a. x - 1/10 = 1/15 b. -4/21 - x = -3/7 c. x + 1/2 = 3/4 - (-1/2) d. 4/7 - x = 1/3 - (-2/3)
mk viết kiểu này 2/3 là 2 phần 3 nha
Giúp mk lun nha mk cần gấp lắm
Tính :
a) \(\dfrac{-1}{21}+\dfrac{-1}{28}\) b) \(\dfrac{-8}{18}-\dfrac{15}{27}\)
c) \(\dfrac{-5}{12}+0,75\) d) \(3,5-\left(-\dfrac{2}{7}\right)\)
BT2; Tính
a,\(\frac{3}{5}\)+\(\frac{-1}{3}\)
b,\(\frac{-2}{13}\)+\(\frac{-11}{26}\)
c,-2+\(\frac{-5}{8}\)
d,\(\frac{13}{30}\)-\(\frac{1}{5}\)
e,\(\frac{2}{21}\)-\(\frac{-1}{28}\)
Tinh:
\(\dfrac{7}{8}.\left(\dfrac{2}{12}+\dfrac{4}{10}\right)\)
\(\dfrac{3}{2}-\dfrac{5}{6}:\left(\dfrac{1}{2}\right)^2+\sqrt{4}\)
\(\dfrac{15}{34}+\dfrac{7}{21}+\dfrac{19}{34}-1\dfrac{15}{17}+\dfrac{2}{3}\)
\(\left(-2\right)^3.\left(\dfrac{3}{4}-0,25\right):\left(2\dfrac{1}{4}-1\dfrac{1}{6}\right)\)
\(16\dfrac{2}{7}:\left(-\dfrac{3}{5}\right)+28\dfrac{2}{7}:\left(-\dfrac{3}{5}\right)\)
Tinh:
a) \(\dfrac{7}{8}.\left(\dfrac{2}{12}+\dfrac{4}{10}\right)\)
b) \(\dfrac{3}{2}-\dfrac{5}{6}:\left(\dfrac{1}{2}\right)^2+\sqrt{4}\)
c) \(\dfrac{15}{34}+\dfrac{7}{21}+\dfrac{19}{34}-1\dfrac{15}{17}+\dfrac{2}{3}\)
d) \(\left(-2\right)^3.\left(\dfrac{3}{4}-0,25\right):\left(2\dfrac{1}{4}-1\dfrac{1}{6}\right)\)
e) \(16\dfrac{2}{7}:\left(-\dfrac{3}{5}\right)+28\dfrac{2}{7}:\left(-\dfrac{3}{5}\right)\)
GIUP MK T ^ T
B = 3/2 - 2/21 - { 7/12 - [ 15/21 - ( 1/3 - 5/4 ) - ( 2/7 + 1/3 )]}
Giải nhanh giúp mình với ạ mình đang cần gấp
1.Tìm x, biết:
a) 7/8 + x = 4/7 b) 6 – x = (-3)/4 c) 1/(-5) + x = 3/4 d) –6 – x = (-3)/5
e) - 2/6 + x = 5/7 f) -8 – x = (-5)/3 g) - 2/10 – x = - 9/8 h) 8 – x = (-1)/6
i) - 2/5 + x = 5/7 j) -2 – x = (-5)/3 k) - 1/6 – x = - 9/8 l) 8 – x = (-1)/5
2. Tính:
a) -7/3 + 4/9 b) -8/18 - 15/56 c) (-7) - (-3/4) d) 0,15 + (-5/12)
e) -1/42 + -1/28 f) -1/21 + -1/36 g) 5,5 - (-2/7) h) 0,9 - (-4/7)
Thực hiện phét tính:
c) \(1\frac{4}{23}+\frac{5}{21}-\frac{4}{23}+0,5+\frac{16}{21}\)
