1. Tính \(\frac{A}{B}\) biết:
a, A=\(\frac{1}{199}+\frac{2}{198}+...+\frac{199}{1}\)
B=\(\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+...+\frac{1}{200}\)
b, A=\(\frac{1}{1.400}+\frac{1}{2.401}+\frac{1}{3.402}+...+\frac{1}{101.500}\)
B=\(\frac{1}{1.102}+\frac{1}{2.103}+\frac{1}{3.104}+...+\frac{1}{399.500}\)