A mathematician and business analyst who says he has worked out the formula for a successful marriage is now helping couples stay together.

Jürgen Schmechel, 58, and wife Ingrid Messner, 54, who celebrate their 25th wedding anniversary this year, said he was always being asked for advice by friends.

Concerned about the breakdown of many marriages of people he knew, he decided on a career change as a relationship expert.

He said his business Inspiring Relationships had already helped 10 couples get on the right track via his no-nonsense workshops and online courses, ‘since opening a year ago.

“I’ve seen so many marriages falter so I know my wife and I were doing something right,” the North Manly father of two said. “I think there is a formula for having a loving relationship mainly based around three aspects: quality time, talking and sex.

“It may seem a strange career switch but I have been successful in my other business and now I want to give something back,”

He said he was not a counsellor but had practical tools and a list of rules to inspire couples. “I am German and I follow the rules and I spell it out like it is,” Mr Schmechel said.

His business-sounding advice includes investing in the relationshop by spending quality time together and to do this couples need to schedule weekly appointments. He said people should also ditch their mobiles and start talking.