Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a) \(\dfrac{5}{9}+\dfrac{13}{7}+\dfrac{15}{13}+\dfrac{8}{7}+\dfrac{4}{9}+\dfrac{11}{13}\)
\(=\left(\dfrac{5}{9}+\dfrac{4}{9}\right)+\left(\dfrac{13}{7}+\dfrac{8}{7}\right)+\left(\dfrac{15}{13}+\dfrac{11}{13}\right)\)
\(=1+3+2\)
\(=6\)
b) \(\dfrac{3}{5}+\dfrac{18}{9}+\dfrac{4}{10}\)
\(=0,6+2+0,4\)
\(=\left(0,6+0,4\right)+2\)
\(=1+2\)
\(=3\)
\(a\dfrac{5}{9}+\dfrac{4}{9}+\dfrac{13}{7}+\dfrac{8}{7}+\dfrac{15}{13}+\dfrac{11}{13}=\dfrac{9}{9}+\dfrac{21}{7}+\dfrac{26}{13}=1+3+2=6\)
a) 7/15+14/15+13/15=(7/15+13/15)+14/15=20/15+14/15=34/15
b)13/4+4/9+7/8=(13/4+7/8)+4/9=(26/8+7/8)+4/9=33/8+4/9=297/72+32/72=329/72
a. 7/15 + 14/15 + 13/15
= 7+14+13/ 15
= 34/15
b.13/4 + 4/9 + 7/8
= [ 13/4 + 7/8 ] + 4/9
= [ 26/8 + 7/8 ] + 4/9
= 33/8 + 4/9
= 297/72 + 32/72
= 329/72
\(=\dfrac{5}{9}\times\dfrac{7}{4}+\dfrac{13}{9}\times\dfrac{7}{4}\\ =\left(\dfrac{5}{9}+\dfrac{13}{9}\right)\times\dfrac{7}{4}\\ =2\times\dfrac{7}{4}\\ =\dfrac{7}{2}\)
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20
=(1+19)+(2+18)+(3+17)+(4+16)+(5+15)+(6+14)+(7+13)+(8+12)+(9+11)+20+10
=20+20+20+20+20+20+20+20+20+20+10
=20×10+10
=200+10
=210
= ( 1 + 19 ) + ( 2 + 18 ) + ( 3 + 17 ) + (4 + 16 ) + ( 5 + 15 ) + ( 6 + 14 ) + ( 7 + 13 ) + ( 8 + 12) + ( 9+ 11 ) + 20
= 20 + 20 + 20 +20 + 20 +20 + 20 + 20 + 20 +20
= 20 x 10
= 200
tui đầu tiên đó
a, = \(\frac{11}{21}\)x \(\left(\frac{7}{4}+\frac{5}{4}\right)\)
= \(\frac{11}{21}\)x 3
= \(\frac{33}{21}\)
b) = \(\left(\frac{23}{14}-\frac{9}{14}\right)\)x \(\frac{6}{13}\)
= 1 x \(\frac{6}{13}\)
= \(\frac{6}{13}\)
dhfwjrfsdkjbskndksjldkfnvkrfghnkjfhwkjfhwk fjghalkuerfgebkrfhjedhksejhlkjrhwejhrbhejrkfljrhebrhfejljrheklruhlwkuiytowhrjeklrjhgs.kjrw3ilvhwiort4jhkw3hr4kjthekjhrtlwejhtlrbvkwytgvkuwehltvgikehrltuiwyhlbiuvyhlitbhlwwncttolwy4twkthnwcjrhtw.ktvjhb q.tilhywcb.wcb.rvyhf.gvniyqt8ot8ot8ot8oy;weniweniweniweniweniweniweniweniweniweniweniwenifh.asklbghsbjkvhagkle/vm sgjfvbklhdfklagh/vekjjjr;klgbjal/bgujrvkll/anwko;tgj/vbal/skjgbkrvjgka.
tính bằng cách thuận tiện nhất
a,4/15 x 7/8 + 4/15 x 2/9
b, 13/29 x 23/11 -13/19 x 8/11 - 13/19 x 4/11
`a: =(7/3-4/3)+11/5=16/5`
`b: =(18/13-5/13)+55/46=1+55/46=101/46`
`c: =27/25-4/9-2/25+5/9=(27/25-2/25)+(5/9-4/9)=1+1/9=10/9`
a,17/23 + (1 - 17/23)
= 17/23 + 6/23
= 23/23 = 1
b,17/12 + 9/7 - (2/7 + 5 /12)
= (17/12 - 5/12) + (9/7 + 2/7)
= 1+1 = 2
c, 7/13 - ( 4/7 -6/13 )
= 7/13 - 4/7+ 6/13
= (7/13 + 6/13) -4/7
= 13/13 -4/7
= 1 -4/7 = 3/7
hok tốt✍️ ✍️
a) 17/23+(1-17/23)
=17/23+1-17/23
=1
b)17/12+9/7-(2/7+5/12)
=17/12+9/7-2/7-5/12
=1+1
=2
c)
7/13-(4/7-6/13)
=7/13-4/7+6/13
=1-4/7
=3/7
Phép tính của em đâu rồi em nhỉ?
Tính bằng cách thuận tiện nhất
\(\dfrac{5}{9}+\dfrac{13}{7}+\dfrac{15}{13}+\dfrac{8}{7}+\dfrac{4}{9}+\dfrac{11}{13}\)
\(=\left(\dfrac{5}{9}+\dfrac{4}{9}\right)+\left(\dfrac{13}{7}+\dfrac{8}{7}\right)+\left(\dfrac{15}{13}+\dfrac{11}{13}\right)\)
\(=1+3+2\\ =6\)