Tính \(\frac{21}{3.10}+\frac{15}{10.15}+\frac{27}{15.24}+\frac{9}{24.2}+\frac{33}{27.38}\)
Cho biểu thứcA= \(\frac{\frac{1}{3.8}+\frac{1}{8.13}+...+\frac{1}{33.38}}{\frac{21}{3.10}+ \frac{15}{10.15}+\frac{27}{15.24}+\frac{9}{24.27}+\frac{33}{27.38}}\)
a,Tính A
b,So snah A và B với B=\(\frac{1}{4}+\frac{1}{9}+\frac{1}{16}+...+\frac{1}{81}+\frac{1}{100}\)
\(\frac{5-\frac{5}{3}+\frac{5}{9}-\frac{5}{27}}{8-\frac{8}{3}+\frac{8}{9}-\frac{8}{27}}:\frac{15-\frac{15}{11}+\frac{15}{121}}{16-\frac{16}{21}+\frac{16}{121}}\)
Bài này bạn tính thôi
Trình bày ra
Rồi làm thôi
Áp dụng công thức tính phân số ở Tiểu học
\(Tính:\) \(\frac{21}{54}+\frac{3}{75}:\frac{\left(\frac{39}{65}+0,415-\frac{33}{600}\right):\frac{21}{9}}{7^2-18,25+13\frac{15}{36}-16\frac{17}{102}}\)
tính
\(\frac{-1}{3}+\frac{0,2-0,3+\frac{5}{11}}{-0,3+\frac{9}{16}-\frac{15}{12}}\)
tìm x :
\(\frac{29-x}{21}+\frac{27-x}{23}+\frac{25-x}{25}+\frac{23-x}{27}+\frac{21-x}{29}=0\)
giúp mình nhé thanks
29-x/21 + 27-x/23 + 25-x/25 + 23-x/27 + 21-x/29 = -5
1 + 29-x/21 + 1 + 27-x/23 + 1 + 25-x/25 + 1 + 23-x/27 + 1 + 21-x/29 = 0
50-x/21 + 50-x/23 + 50-x/25 + 50-x/27 + 50-x/29 = 0
(50-x) (1/21 + 1/23 + 1/25 + 1/27 + 1/29) = 0
Vì: 1/21 + 1/23 + 1/25 + 1/27 + 1/2 > 0
=> 50 - x = 0
x = 50
Vậy x = 50
\(\frac{-1}{3}+\frac{0,2-0,3+\frac{5}{11}}{-0,3+\frac{9}{16}-\frac{15}{12}}\)
\(=\frac{-1}{3}+\frac{\frac{2}{10}-\frac{3}{10}+\frac{5}{11}}{\frac{-3}{10}+\frac{9}{16}-\frac{15}{12}}\)
\(=\frac{-1}{3}+\frac{\frac{39}{110}}{\frac{-79}{80}}\)
\(=\frac{-1}{3}-\frac{312}{869}\)
\(=\frac{-1805}{2607}\)
Tính nhanh:
B=\(\left(\frac{11}{4}.\frac{-5}{9}-\frac{4}{9}:\frac{4}{11}\right).\frac{8}{33}\)
C=\(\frac{1}{10}+\frac{1}{15}+\frac{1}{21}+...+\frac{1}{120}\)
Tính giá trị biểu thức
\(1.A=\frac{1}{5}+\frac{3}{17}-\frac{4}{3}+\left(\frac{4}{5}-\frac{3}{17}+\frac{1}{3}\right)-\frac{1}{7}+\left[\frac{-14}{30}\right]\)
\(2.B=\left(\frac{5}{8}-\frac{4}{12}+\frac{3}{2}\right)-\left(\frac{5}{8}+\frac{9}{13}\right)-\left[\frac{-3}{2}\right]+\frac{7}{-15}\)
\(3.C=\frac{5}{18}+\frac{8}{19}-\frac{7}{21}+\left(\frac{-10}{36}+\frac{11}{19}+\frac{1}{3}\right)-\frac{5}{8}\)
\(4.D=\frac{1}{9}-\left[\frac{-5}{23}\right]-\left(\frac{-5}{23}+\frac{1}{9}+\frac{25}{7}\right)+\frac{50}{14}-\frac{7}{30}\)
\(5.E=\frac{1}{13}+\left(\frac{-5}{18}-\frac{1}{13}+\frac{12}{17}\right)+\left(\frac{12}{17}+\frac{5}{18}+\frac{7}{5}\right)\)
\(6.F=\frac{15}{14}-\left(\frac{17}{23}-\frac{80}{87}+\frac{5}{4}\right)+\left(\frac{12}{17}-\frac{15}{14}+\frac{1}{4}\right)\)
\(7.G=\frac{1}{25}-\frac{4}{27}+\left(\frac{-23}{27}+\frac{-1}{25}-\frac{5}{43}\right)+\frac{5}{43}-\frac{4}{7}\)
\(8.H=\frac{4}{15}-\frac{23}{28}-\left(\frac{-23}{28}+\frac{-11}{15}-\frac{29}{27}\right)-\frac{2}{27}\)
\(9.K=\frac{1}{16}-\frac{5}{21}+\left(\frac{-1}{16}+\frac{-3}{5}-\frac{-5}{21}\right)+\frac{-2}{5}+\frac{3}{4}\)
\(10.L=\frac{7}{12}+\frac{15}{14}-\left(\frac{14}{22}+\frac{-1}{14}+\frac{5}{21}\right)-\frac{-5}{21}+\frac{3}{5}\)
yutyugubhujyikiu
tính: \(\frac{21}{54}\)+\(\frac{3}{75}\):\(\frac{\left(\frac{39}{65}\right)+0,145-\frac{33}{600}:\frac{21}{9}}{7^2-18,25+3\frac{15}{36}-16\frac{17}{102}}\)
đóng ngoặc tron ở p/s 39/65 va 33/600
giúp mk nhé
21/54 + 3/75 : (39/65) + 29/200 - ( 33/600 ) : 21/9 / 7^2 - 73/4 + 41/12 - 97/6
= 21/54 + 3/75 : (39/65) + 29/200 - 33/600 . 9/21 / 49 - 73/4 + 41/12 - 97/6
= 21/54 + 3/75 : 149/200 - 33/1400 / 49 - 73/4 + ( -51/4 )
= 21/54 + 3/75 : 101/140 / 123/4 + ( -51/4 )
= 21/54 + 3/75 : 101/140 / 18
= 21/54 + 3/75 : 101/140 . 1/18
= 21/54 + 3/75 : 101/2520
= 21/54 + 3/75 . 2520/101
= 21/54 + 504/505
Tim hai so tu nhiên a,b toa man dieu kien a+2b=48 va (a,b)+3=144
\(\frac{21}{54}+\frac{3}{75}:\frac{\left(\frac{39}{65}+0,415-\frac{33}{600}\right):\frac{21}{9}}{7^2-18,25+13\frac{15}{16}-16\frac{17}{102}}\)
Rút gọn
A)\(\frac{26}{60}+\frac{3}{15}\)
B)\(\frac{4}{26}+\frac{33}{78}\)
C)\(\frac{25}{40}-\frac{3}{12}\)
D)\(\frac{21}{27}+\frac{10}{54}+\frac{5}{15}\)
\(a,\frac{26}{60}+\frac{3}{15}=\frac{13}{30}+\frac{1}{5}=\frac{13}{30}+\frac{6}{30}=\frac{19}{30}\)
\(b,\frac{4}{26}+\frac{33}{78}=\frac{2}{13}+\frac{11}{26}=\frac{4}{26}+\frac{11}{26}=\frac{15}{26}\)
\(c,\frac{25}{40}-\frac{3}{12}=\frac{5}{8}-\frac{1}{4}=\frac{5}{8}-\frac{2}{8}=\frac{3}{8}\)
\(d,\frac{21}{27}+\frac{10}{54}+\frac{5}{15}=\frac{7}{9}+\frac{5}{27}+\frac{1}{3}=\frac{21}{27}+\frac{5}{27}+\frac{9}{27}=\frac{35}{27}\)
~Study well~
#Thạc_Trân