a)\(\frac{5}{7}:X=1-\frac{4}{7}=\frac{3}{7}\)
\(X=\frac{5}{7}:\frac{3}{7}=\frac{5}{3}\)
b)
\(\left(\frac{1}{11}-\frac{1}{13}+\frac{1}{13}-\frac{1}{14}+...+\frac{1}{19}-\frac{1}{21}\right)-X=\frac{4}{3}-\frac{221}{231}=\frac{29}{77}\)
\(\left(\frac{1}{11}-\frac{1}{21}\right)-X=\frac{29}{77}\)
\(X=\frac{10}{231}-\frac{29}{77}=-\frac{1}{3}\)
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Tìm x biết (2/11.13+2/13.15+...+2/19.21)-x+ 4+221/231=7/3
tìm x, biết
a, \(\left(\frac{11}{12}+\frac{11}{12.23}+\frac{11}{23.24}+...+\frac{11}{89.100}\right)+x=\frac{5}{3}\)
b, \(\left(\frac{2}{11.13}+\frac{2}{13.15}+...+\frac{2}{19.21}\right)-x+4+\frac{221}{231}=\frac{7}{3}\)
( 2/11.13 + 2/13.15 + ..... + 2/19.21 ) -x + 221/231 =4/3
tìm x biết:
a, (11/12+11/12.23+11/23.24+...+11/89.100)+x=2/3
b, (2/11.13+2/13.15)+...+2/19.21)-x+221/231=4/3
Giúp mk nha ai giải đc mk tick cho nhé!
Tìm x:
\((\frac{2}{11.13}+\frac{2}{13.15}+...+\frac{2}{19.21})-x+\frac{221}{231}=\frac{4}{3}\)
tìm x, biết
2/11.13 + 2/13.15 +........2/19.21 -x + 221/231 = 4/3
help mk vs, nhanh lên nha!
1/Tìm x, biết:
(2/11.13 + 2/13.15 +...+ 2/19.21) - x + 4 + 221/231 = 7/3
a)Tìm số tự nhiên a nhỏ nhất sao cho a chia cho 3, cho 5, cho 7 được số dư thứ tự là 2, 4, 6
b) \(\frac{1}{3}+\frac{3}{35}< \frac{x}{210}< \frac{4}{7}+\frac{3}{5}+\frac{1}{3}\)
c)\(\left(\frac{2}{11.13}+\frac{2}{13.15}+...+\frac{2}{19.21}\right)-x+\frac{221}{231}=\frac{4}{3}\)
Tìm x:
A)11/12+11/12.23+11/23.24+....+11/89.100+x=2/3
B)2/11.13+2/13.15+...+2/19.21-x+221/223=4/3