The study examined several hundred borrowers who held mortgages issued in 2006 and 2007 -- right before the mortgage meltdown. Of the study subjects, 25 percent of the borrowers who scored in the lowest bracket for math skills had defaulted on mortgage payments within five years of getting the loans. Meanwhile, only 5 percent of those in the top tier for math skills defaulted.
The survey sample included homebuyers from a variety of backgrounds, from blue collar workers to corporate professionals. Their math ability covered the gamut -- from those with very limited abilities to a mathematician with a six-figure salary, according to Kristopher Gerardi, an economist with the Federal Reserve of Atlanta.
The researchers controlled for differences in overall intelligence by measuring for verbal and general IQs, as well as math skills, and controlled for socioeconomic factors, such as age, sex, income, ethnicity and local labor market conditions.
Surprisingly, it did not seem to matter what kind of mortgage the borrowers had, the researchers found. "Those lacking [math skills] will still get in more trouble later on even if they pick a plain vanilla mortgage," said Meier.
The researchers asked the survey participants a series of five basic questions. The simplest question asked them how much a $300 sofa would cost at a half-price sale. The most difficult asked how much a savings account of $200 would grow to after earning 10 percent interest for two years.
Determining why those with poor math skills default on mortgages more often than others will take more research, but previous studies suggest that people who struggle with simple math also struggle with handling their finances, according to Gerardi. This group tends to budget less carefully, misuse credit cards and mishandle financial emergencies, such as temporary income losses. When they hit a rough financial patch, they may not understand the math well enough to negotiate the most favorable settlements with lenders.
"When bad events happened, they don't react optimally," said Meier.
More at CNN Money:
Was Your Home a Good Investment?
How Much Do You Know About Mortgages
Inside a 295-Square-Foot Apartment
More on AOL Real Estate:
Find out how to calculate mortgage payments.
Find homes for sale in your area.
Find foreclosures in your area.
Find homes for rent.
Follow us on Twitter at @AOLRealEstate or connect with AOL Real Estate on Facebook.