Bài: Tính theo cách hợp lí:
a) \(\frac{4}{20}+\frac{16}{42}+\frac{6}{15}+\frac{-3}{5}+\frac{2}{21}+\frac{-10}{21}+\frac{3}{20}\)
b) \(\frac{42}{46}+\frac{250}{186}+\frac{-2121}{2323}+\frac{-125125}{143143}\)
Những câu hỏi liên quan
tính theo cách nhanh nhất:
\(\frac{4}{20}+\frac{16}{42}+\frac{6}{15}-\frac{3}{5}+\frac{2}{21}-\frac{10}{21}+\frac{3}{20}\)
\(\frac{42}{46}+\frac{250}{186}-\frac{2121}{2323}-\frac{125125}{143143}\)
Tính
\(\frac{4}{20}+\frac{16}{42}+\frac{6}{15}+\frac{-3}{5}+\frac{2}{21}+\frac{-10}{21}+\frac{3}{10}\)
\(\frac{42}{46}+\frac{250}{186}+\frac{-2121}{2323}+\frac{-125125}{143143}\)
Bài 1: Tính theo cách hợp lí:a/frac{4}{20}+frac{16}{42}+frac{6}{15}+frac{-3}{5}+frac{2}{21}+frac{-10}{21}+frac{3}{20}b/frac{42}{46}+frac{250}{186}+frac{-2121}{2323}+frac{-125125}{143143}Bài 2:Tính tổng các phân số sau:a/ frac{1}{1.2}+frac{1}{2.3}+frac{1}{3.4}+...+frac{1}{2003.2004}b/frac{1}{1.3}+frac{1}{3.5}+frac{1}{5.7}+...+frac{1}{2003.2005}
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Bài 1: Tính theo cách hợp lí:
a/\(\frac{4}{20}+\frac{16}{42}+\frac{6}{15}+\frac{-3}{5}+\frac{2}{21}+\frac{-10}{21}+\frac{3}{20}\)
b/\(\frac{42}{46}+\frac{250}{186}+\frac{-2121}{2323}+\frac{-125125}{143143}\)
Bài 2:Tính tổng các phân số sau:
a/ \(\frac{1}{1.2}+\frac{1}{2.3}+\frac{1}{3.4}+...+\frac{1}{2003.2004}\)
b/\(\frac{1}{1.3}+\frac{1}{3.5}+\frac{1}{5.7}+...+\frac{1}{2003.2005}\)
a ) \(\frac{4}{20}+\frac{16}{42}+\frac{6}{15}+\frac{-3}{5}+\frac{2}{21}+\frac{-10}{21}+\frac{3}{20}\)
\(=\frac{4}{20}+\frac{8}{21}+\frac{2}{5}-\frac{3}{5}+\frac{2}{21}+\frac{-10}{21}+\frac{3}{20}\)
\(=\left(\frac{4}{20}+\frac{3}{20}\right)+\left(\frac{8}{21}+\frac{2}{21}-\frac{10}{21}\right)+\left(\frac{2}{5}-\frac{3}{5}\right)\)
\(=\frac{7}{20}+0+\frac{-1}{5}=\frac{7-4}{20}=\frac{3}{20}\)
b ) \(\frac{42}{46}+\frac{250}{186}+\frac{-2121}{2323}+\frac{-125125}{143143}\)
\(=\frac{21}{23}+\frac{-21}{23}+\frac{-125}{143}\)
\(=0+\frac{-125}{143}=-\frac{125}{143}\)
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bài 2
a \(\frac{1}{1.2}+\frac{1}{2.3}+...+\frac{1}{2003.2004}\)
=\(1-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+...+\frac{1}{2003}-\frac{1}{2004}\)
=\(1-\frac{1}{2004}=\frac{2003}{2004}\)
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a ) \(\frac{1}{1.2}+\frac{1}{2.3}+\frac{1}{3.4}+....+\frac{1}{2003.2004}\)
\(=1-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+.....+\frac{1}{2003}-\frac{1}{2004}\)
\(=1-\frac{1}{2004}=\frac{2003}{2004}\)
b ) \(\frac{1}{1.3}+\frac{1}{3.5}+\frac{1}{5.7}+....+\frac{1}{2003.2005}\)
\(=\frac{1}{2}\left(1-\frac{1}{3}+\frac{1}{3}-\frac{1}{5}+....+\frac{1}{2003}-\frac{1}{2005}\right)\)
\(=\frac{1}{2}\left(1-\frac{1}{2005}\right)=\frac{1}{2}.\frac{2004}{2005}=\frac{1002}{2005}\)
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Xem thêm câu trả lời
a) \(\frac{5}{9}+\frac{x}{-1}=\frac{-1}{3}\)
2. tính theo cách hợp lý
a) \(\frac{4}{20}+\frac{16}{42}+\frac{6}{15}+\frac{-3}{15}+\frac{2}{21}+\frac{-10}{21}+\frac{3}{20}\)
b) \(\frac{42}{46}+\frac{250}{186}+\frac{-2121}{2323}+\frac{-125125}{143143}\)
giúp mih với nha.sẽ nhận đc nhìu like lém đó. help me
Thực hiện phép tính sau :a)11frac{3}{13}-left(2frac{4}{7}+5frac{3}{13}right)b)frac{4}{20}+frac{16}{42}+frac{6}{15}+frac{-3}{5}+frac{2}{21}+frac{-10}{21}+frac{3}{10}c)frac{42}{46}+frac{250}{286}+frac{-2121}{2323}+frac{-125125}{143143}(Giải chi tiết các bạn nhá ^_^!!!)
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Thực hiện phép tính sau :
a)\(11\frac{3}{13}-\left(2\frac{4}{7}+5\frac{3}{13}\right)\)
b)\(\frac{4}{20}+\frac{16}{42}+\frac{6}{15}+\frac{-3}{5}+\frac{2}{21}+\frac{-10}{21}+\frac{3}{10}\)
c)\(\frac{42}{46}+\frac{250}{286}+\frac{-2121}{2323}+\frac{-125125}{143143}\)
(Giải chi tiết các bạn nhá ^_^!!!)
a)11 3/13-(2 4/7+5 3/13)=11+3/13-(2+4/7+5+3/13)=11+3/13-2-4/7-5-3/13=(11-2-5)+(3/13-4/7-3/13)=4+(0-4/7)=4+-4/7=28/7-4/7=28-4/7=24/7=3 3/7(phải tính ta hỗn số nha bn)
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NẾU KO LM` ĐC THÌ NHỜ MIK NHẮN TIN HOẶC GỌI QUA 01288449416 NHA R` MIK LÊN GIẢI CHO.
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\(\text{}\text{}11\frac{3}{13}-\left(2\frac{4}{7}+5\frac{3}{13}\right)=11\frac{3}{13}-2\frac{4}{7}-5\frac{3}{13}=11\frac{3}{13}-5\frac{3}{13}-2\frac{4}{7}=6-2\frac{4}{7}=5\frac{7}{7}-2\frac{4}{7}=3\frac{3}{7}\)
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Tính :
\(\frac{42}{46}+\frac{250}{186}+\frac{-2121}{2323}+\frac{-125125}{143143}\)
\(\frac{42}{46}+\frac{250}{186}+\frac{-2121}{2323}+\frac{-125125}{143143}\Leftrightarrow\frac{21}{23}+\frac{125}{93}+\frac{-21}{23}+\frac{-125}{143}\)
\(\Rightarrow\left(\frac{21}{23}+\frac{-21}{23}\right)+\left(\frac{125}{93}+\frac{-125}{143}\right)=\frac{17000}{3999}\)
Tính tổng
\(\frac{42}{46}+\frac{250}{186}+\frac{-2121}{2323}+\frac{-125125}{143143}\)
\(\frac{4}{46}+\frac{250}{186}+\frac{-2121}{2323}+\frac{-125125}{143143}=\frac{2}{23}+\frac{125}{93}-\frac{21}{23}-\frac{125}{143}\)
\(=-0,36\)
Nhơ nha bạn.Tích mình mình tích lại
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Tính theo cách hợp lí:
a/ 4/20+16/42+ 6/15+ -3/5 +2/21+ -10/21+3/20
b/ 42/46+ 250/186+ -2121/2323+ -125125/143143
a, \(\frac{4}{20}+\frac{16}{42}+\frac{6}{15}+\frac{-3}{5}+\frac{-10}{21}+\frac{3}{20}\)
\(=\left(\frac{4}{20}+\frac{-3}{5}+\frac{6}{15}+\frac{3}{20}\right)\)\(+\left(\frac{16}{42}+\frac{2}{21}+\frac{-10}{21}\right)\)
\(=\left(\frac{4}{20}+\frac{-12}{20}+\frac{8}{20}+\frac{3}{20}\right)\)\(+\left(\frac{8}{21}+\frac{2}{21}+\frac{-10}{21}\right)\)
\(=\frac{3}{20}\)
b,\(\frac{42}{46}+\frac{250}{186}+\frac{-2121}{2323}+\frac{-125125}{143143}\)
\(=\frac{21}{23}+\frac{125}{93}+\frac{-21}{23}+\frac{-125}{143}\)
\(=\left(\frac{21}{23}+\frac{-21}{23}\right)+\left(\frac{125}{93}+\frac{-125}{143}\right)\)
\(=\frac{6250}{13299}\)
TÍNH HỢP LÝ
a, \(\frac{-7}{21}+\left(1+\frac{1}{3}\right)\)
b,,,,, \(\frac{42}{46}+\frac{250}{286}+\frac{-2121}{2323}+\frac{-125125}{143143}\)