A housewife didn't know how to estimate the cost of living, so she asked her husband about it。Her husband said, "It's very simple. Take our income and add 30 per cent."有个家庭主妇不知道怎样估算他们的生活费用，就去问她的丈夫。她的丈夫说：“很简单。就是把我们的收入另外加30%”