Tính ttoorrng :
a) (-17) + 5 + 8 + 17;
b) 30 + 12 + (-20) + (-12)
c) (-4) + (-440) + (-6) + 440;
d) (-5) + (-10) + 16 + (-1)
Tính một cách hợp lý : \(\dfrac{5}{17}.\dfrac{7}{11}+\dfrac{5}{17}.\dfrac{4}{11}+\dfrac{-12}{17}\) là
A. \(\dfrac{17}{-17}\) B. \(\dfrac{8}{17}\)
C. \(\dfrac{-7}{17}\) D. \(-\dfrac{-7}{17}\)
\(\dfrac{5}{17}\left(\dfrac{7}{11}+\dfrac{4}{11}\right)-\dfrac{12}{17}=\dfrac{5}{17}\times1-\dfrac{12}{17}=\dfrac{5}{17}-\dfrac{12}{17}=-\dfrac{7}{17}\)
tính nhanh: A=2/7 + -3/ 8 + 11/7 + 1/ 3 + 1/ 7 + 5 / -8; B=3/17 + -5/ 13 + -18/35 + 14/ 17 + 17
\(A=\frac{2}{7}+\frac{-3}{8}+\frac{11}{7}+\frac{1}{3}+\frac{1}{7}+\frac{5}{-8}\)
\(A=\left(\frac{2}{7}+\frac{11}{7}+\frac{1}{7}\right)+\left(\frac{-3}{8}+\frac{5}{-8}\right)+\frac{1}{3}\)
\(A=2-1+\frac{1}{3}\)
\(A=\frac{4}{3}\)
\(B=\frac{3}{17}+\frac{-5}{13}+\frac{-18}{35}+\frac{14}{17}+17\)
\(B=\left(\frac{3}{17}+\frac{14}{17}\right)+\frac{-5}{13}+\frac{-18}{35}+17\)
\(B=1+\frac{-5}{13}+\frac{-18}{35}+17\)
\(B=18+\frac{-5}{13}+\frac{-18}{35}\)
\(B=\frac{7781}{455}\)
tính tổng : a) (-17)+5+8+17
(-17) + 5 + 8 + 17
= ( -17) + 17 + 5 + 8
= 0 + 5 + 8
= 13
tick nha
( - 17 ) + 5 + 8 + 17
= ( - 17 ) + 17 + 5 + 8
= 0 + 5 + 8
= 5 + 8
= 13
tick tớ nha bạn !
bài 1 Tính:
a) 5/17 * 8/-7+8/17*-7/3+-7/3*4/17
b) -10/13 + 5/17 - 3/13 + 12/17 - 11/20
giúp tớ vs ạ. Tớ CẢM ƠN
*tớ thêm một câu nữa ạ
c) 5/9 * 7/13 + 5/9 * 9/13 + 3/13 * -5/9
a) 5/17 * 8/-7+8/17*-7/3+-7/3*4/17
-40/119 + 12/17 × -7/3
-40/119 + -28/17 =-236/119
b) -10/13 + 5/17 - 3/13 + 12/17 - 11/20
(5/17+12/17)-(10/13+3/13)-11/20
-11/20
a) 5/17 * 8/-7+8/17*-7/3+-7/3*4/17
-40/119 + 12/17 × -7/3
-40/119 + -28/17 =-236/119
b) -10/13 + 5/17 - 3/13 + 12/17 - 11/20
(5/17+12/17)-(10/13+3/13)-11/20
-11/20
tính nhanh
a, -5/9+8/18+-2/11+4/-9+7/15
b, 5/17+-9/15+-2/17+2/5+14/17
a,-5/9 + 8/18 + -2/11 + 4/-9 + 7/15 b,5/17 + -9/15 + -2/17 + 2/5 + 14/17
= -5/9 + 4/9 + -2/+ 4/-9 + 7/15 = 5/17 + -3/5 + -2/17 + 2/5 + 14/17
=(-5/9 + 4/9 + -4/9 ) +-2/11 + 7/15 = ( 5/17 + -2/17 + 14/17) + ( 2/5 + -3/5)
= -1/3 + -2/11 + 7/15 =1 + -1/5
=-75/225 + -30/ 225 + 77/225 =4/5
= -25/225 = -1/9 ( 4/5 = 0.8 )
gúp mik
1) tính. (1đỉm)
a) 6/17 + 13/17 b) 5 x 8/20\(a)\dfrac{6}{17}+\dfrac{3}{17}\)
\(=\dfrac{6+13}{17}\)
\(=\dfrac{19}{17}\)
\(b)5\times\dfrac{8}{20}\)
\(=5\times\dfrac{2}{5}\)
\(=\dfrac{10}{5}\)
\(=2\)
_HT_
Thực hiện phép tính:
a. (-17)+5+8+17+( -3 )
b. (5 mũ 19/ 5 mũ 17+3 ) / 7
c.| -8 |+(-5) +9+(-7) +| -4|
d.1-2+3-4+...+2011-2012
Tính giá trị biểu thức A = 8 3/17. 5 1/4 +3 14/17 . 5 1/4 / ( 1 14/17 - 1 1/34) . 34
a: =35/17-18/17-9/5+4/5
=1-1=0
b: =-7/19(3/17+8/11-1)
=7/19*18/187=126/3553
c: =26/15-11/15-17/3-6/13
=1-6/13-17/3
=7/13-17/3=-200/39