Question

[Nguyễn Minh Sơn]

Tìm x, biết: \(\frac{3x}{2.5}\)+\(\frac{3x}{5.8}\)+\(\frac{3x}{8.11}\)+\(\frac{3x}{11.14}\)=\(\frac{1}{21}\)

Answer 1

[giang ho dai ca]

x. [3/2.5 +3/5.8+ 3/8.11+3/11.14] = 1/21

=> x . [1/2-1/5+1/5-1/8+1/8-1/11+1/11-1/14] = 1/21

=> x. [1/2-1/14] = 1/21 => x . 3/7= 1/21 

=> x = 1/9

Answer 2

[Bùi Đức Anh]

x. [3/2.5 +3/5.8+ 3/8.11+3/11.14] = 1/21

=> x . [1/2-1/5+1/5-1/8+1/8-1/11+1/11-1/14] = 1/21

=> x. [1/2-1/14] = 1/21 => x . 3/7= 1/21 

=> x = 1/9

mình nhé