Sometimes (oftentimes) numbers don't make sense ?- to me at least. Oh sure, two plus two equals four and numbers are unchangeable so they should follow logical standards. But they don't. Therein lies the mystery.

Let's start with gas - of the gallon variety. Why is gas priced at a certain amount plus nine-tenths of a cent? Nothing else is priced this way. Not other things we buy by the gallon - like milk or water or whisky.

More decimal dilemmas: radio station numbers go one digit beyond the decimal point, but their radio jingle will round up or down to get to a whole number so 94.9 becomes 95 and 92.3 becomes 92. While I recognize the importance of a catchy jingle, it seems like this could cause confusion for listeners looking for a certain station.

Having a pair of something means two items: a pair of dice, a pair of aces, a pair of socks and a pair of shoes for instance. But a pair of pants is just one piece of clothing. Would two pants be a pair of a pair of pants? How about a pair of twins: is that four people or two?

Races are measured in distance, but why is a 5-K measured in kilometers and a marathon measured in miles? The lack of consistency is off-putting, and I'm not even a runner.

Thinking further, why is it 26.2 and 13.1? After running 26 or 13 miles is it really necessary to run another thousand feet in order to earn the window cling?

Why pick mile marker 13 as a benchmark at all? The number 13 is associated with bad karma ?- especially if the race is on a Friday. Hotels have been known to skip the entire thirteenth floor because the number is thought to be bad luck, which doesn't make sense because that just makes the fourteenth floor bad luck.

While we're skipping numbers (not rocks) let's look at the months of the year. Four of them have 30 days, seven have 31 and then there's February with the odd, albeit even, 28 - or every four years an equally odd 29. It doesn't make sense to have one month with 28 when it would be neater and more consistent to have seven months with 30 and five with 31, except for leap years, which would be an even more consistent six and six.

Then there are the numbers as related to shoe sizes. Here in the U.S. a man's size seven is equal to a woman's size nine. The European equivalent is 42, except in the UK, which has a system all its own. (Of course it does.) None of the varying sizing options coordinates with inches or centimeters, which seems like the most logical option. Having a shoe size of 10 inches or 26 centimeters makes simple sense, but numbers are hardly ever simple.

This complex truth is demonstrated in sports scores. In basketball, a basket gets your team two points, unless it is a three pointer. Free throws earn one point each. A touchdown in football is worth six points, a field goal three and a safety two. An extra point is just that, unless you go for two. In hockey three goals equals a hat trick. In baseball three strikes makes you out. Four balls get you to first base. A home run gets you anywhere from one to four runs. In tennis love is zero. In soccer zero is zero.

Beyond sports scores, there are four quarters in football and basketball, which is the equivalent to two halves in soccer. A game of hockey consists of three periods, while baseball has nine innings. A tennis match has two or three sets, which contain anywhere from six to a gazillion games each, depending. It's enough to make my head spin.

A rational person understands numbers are a useful and necessary part of life. They help us calculate distance and tell us if we have enough money to pay the mortgage. They dictate ingredient amounts in recipes. They give us information about shoe and pant sizes. They fill calendars and scoreboards.

Despite their proliferation, numbers can be vexing and complicated, for some of us, at least. You'd think there'd be some comfort in knowing two plus two equals four - and there is. But beyond that sometimes things just don't add up.

Jill Pertler is an award-winning syndicated columnist, published playwright, author and member of the National Society of Newspaper Columnists. Don't miss a slice; follow the Slices of Life page on Facebook.