Question

[Nguyễn Văn Đức]

1.Tìm x, biết:

a.\(\frac{1}{2}\)x\(x\)+\(\frac{2}{3}\)=\(\frac{5}{2}\)

b.\(\frac{x}{12}\)+\(\frac{5}{24}\)=\(\frac{5}{6}\)

c.(1234+\(x\)+766)x0,25=6,2:0,01

2.Tính bằng cách hợp lý.

A=\(\frac{1}{2}\)x\(\frac{5}{7}\)+\(\frac{9}{7}\)x0,3+\(\frac{1}{2}\)x\(\frac{4}{7}\)+\(\frac{9}{4}\)+\(\frac{9}{7}\)x0.2

B=\(\frac{2002\cdot15-1}{2001+2002\cdot14}\)