9/5: 17/5 +8/5:17/15 b 100/ + 28,4/-36,7/
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
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 )
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
A) cách 1\(\frac{9}{5}:\frac{17}{15}+\frac{8}{5}:\frac{17}{15}\)
\(=\frac{9}{5}\cdot\frac{15}{17}+\frac{8}{5}\cdot\frac{15}{17}\)
\(=\frac{135}{85}+\frac{120}{85}\)
\(=\frac{255}{85}\)
\(=3\)
Cách 2\(\frac{9}{5}:\frac{17}{15}+\frac{8}{5}:\frac{17}{15}\)
\(=\frac{9}{5}\cdot\frac{15}{17}+\frac{8}{5}\cdot\frac{15}{17}\)
\(=\frac{15}{17}\cdot\left(\frac{9}{5}+\frac{8}{5}\right)\)
=\(\frac{15}{17}\cdot\frac{17}{5}\)
\(=\frac{15\cdot17}{17\cdot5}\)
\(=\frac{5\cdot3\cdot17}{17\cdot5}\)
\(=3\)
B) Cách 1 :
0,9 : 0,25 + 1,05 : 0,25
= 3,6 + 4,2
=7,8
Cách 2:
0,9 : 0,25 + 1,05 : 0,25
\(=0,9:\frac{1}{4}+1,05:\frac{1}{4}\)
\(=0,9\cdot4+1,05\cdot4\)
\(=4\cdot\left(0,9+1,05\right)\)
\(=4\cdot1,95\)
=\(7,8\)
9/5 : 17/15 + 8/5 : 17/15= 17/15 : ( 9/5 + 8,5 )
= 17/15 : 17/5
= 1/3
\(\frac{9}{5}:\frac{17}{15}+\frac{8}{5}:\frac{17}{15}=\frac{9}{5}.\frac{15}{17}+\frac{8}{5}.\frac{15}{17}=\frac{15}{17}\left(\frac{9}{5}+\frac{8}{5}\right)=\frac{15}{17}.\frac{17}{5}=3\)
\(\frac{9}{5}:\frac{17}{15}+\frac{8}{5}:\frac{17}{15}\)= \(\left(\frac{9}{5}+\frac{8}{5}\right):\frac{17}{15}\)
=\(\frac{17}{5}.\frac{15}{17}\)= 3
9/5:17/15+8/5:17/15
=(9/5+8/5):17/15
=17/5:17/15
=3
Chúc bạn học giỏi nha!!!
K cho mik vs nhé Tuyên
a) Ta có: \(\dfrac{9}{5}:\dfrac{17}{5}+\dfrac{8}{5}:\dfrac{17}{15}\)
\(=\dfrac{9}{5}\cdot\dfrac{5}{17}+\dfrac{8}{5}\cdot\dfrac{15}{17}\)
\(=\dfrac{9}{17}+\dfrac{24}{17}=\dfrac{33}{17}\)
a )9/5: 17/5 + 8/5 : 17/15 = 9/5 x 5/17 + 8/5 x 15/17 = 9/17 +24/17= 33/17
b) ?