Question

Tính nhanh: 989898/454545 - 31313131/15151515

Answer 1

\(\dfrac{989898}{454545}-\dfrac{31313131}{15151515}=\dfrac{98\cdot10101}{45\cdot10101}-\dfrac{31\cdot1010101}{15\cdot1010101}\\ =\dfrac{98}{45}-\dfrac{31}{15}=\dfrac{98-31\cdot3}{45}=\dfrac{5}{45}=\dfrac{1}{9}\)

Answer 2

\(\dfrac{1}{9}\)