The ratio of the ages of man and his wife is 4:3. After 4 years, the ration will be 9:7. If at the time of marriage, the ratio was 5:3, how many years agowere they married?
In a certain code language, 'x' represents '+', '÷' represents 'x', '-' represents '÷' and '+' represents '-'. Find out the answer to the following question.