Why are men smarter than women?

Here is the story my ex started dating on the internet. There was guy who said he made $200,000.00 a year but all his pics were of him in his 10 year old car and ratty apartment with old furniture. I said the guy was a liar my boss made 300k a year and had a Mercedes s-cl and 5000 square foot house. I explained this to my ex. She didn't want to believe this guy was a liar I asked her if she was making 200k a year would she be driving an old car with a dent in the side. She still believed him! Is their a reason why women are not smart as men and more easily lied too? Or lack common sense?