1吨 = 1000 千克2500千克 = （2500÷1000）吨= 5/2 吨 = 2分之5吨2/7 x =4x = 4 ÷ 2/7 = 4 * 7/2 = 14x - 1/3 x = 7/172/3 x = 7/17x = 7/17 ÷ 2/3= 7/17 * 3/2= (7*3)/(17*2)= 21 / 34