One has good reason to be suspicious of decimals, particularly when private companies are out to milk you for your last paisa when they bill you

Imagine how much simpler our school arithmetic would have been if we were allowed to calculate like the gas cylinder delivery man. Sums are a doddle when you round off decimal points to the nearest integer. Don’t know what an integer is? Sorry, I didn’t realise you were mathematically challenged. It’s a whole number. No fractions involved, comprende? Anyway, before I come to the gas man who, like god, works in mysterious ways, let me tell you about how dodgy decimals have been sneaking their way into many regions of my existence.

I recently ate a veg pakora that cost Rs 2.62. To be more precise, I shared a plate of five with a friend, and it cost us Rs 13.10. (Quick, do the division, children, and check my answer.) I would say that’s pretty reasonable for a joint on Church Street. Where’s the catch? Our two coffees cost Rs 48.91. So you’d better buy a cheap beverage somewhere else if you wish to take full advantage of the bargain price of pakoras which, incidentally, are not their usual tiny, dishevelled selves but resemble large cutlets and are crisp though not oily. Did you notice how I’ve smartly thrown you off the scent? Look once more at the cost of two coffees — there’s no way that amount can be realistically divided by two! When I scrutinised the bill I found that the decimals in the weird total of 62.01 were taken care of with the convenient addition of a VAT of 8.99, so that the grand total was rounded off to 71. The whole transaction does smell fishy, but the place seems legit enough, with extremely friendly waiters who appear to be from Bihar or 24 Parganas, and whose help you will need to snip open the packets of sauce (all that and unlimited sauce, too, for 13.10).

Being innately chary of both decimals and technology, I used to keep tabs on the money withdrawn from my smart card in the early days of my using the metro. Since the card knocks a certain percentage off the fare the numbers displayed are all peppered with decimal points: for instance, you are charged Rs 12.25 from one terminal to the other. Fearing that the turnstile would cheat me, I would memorise the figure that appeared when I clocked in and, failing to do the math in my head (try subtracting 12.25 from 101.05), would scribble the number in my notepad at the first opportunity and work out the amount that was to be displayed when I exited. Then, I took to calculating the fare to stations in between. I once noted down in my pad that a ride from Byappanahalli to Trinity cost me Rs 11.05. I also noted (mentally — I didn’t need pen and paper for this one) that the ride took 11 minutes, from 6.39 to 6.50, according to the overhead monitor inside the coach.

One has good reason to be suspicious of decimals, particularly when private companies are out to milk you for your last paisa when they bill you. A credit card company once charged a cardholder interest on the entire amount on his bill because it refused to accept that the five paise in the total should be rounded off to the lower and not higher rupee. Here you’ve got to hand it to the government: it faithfully follows the norm by forgoing all chutta below 50 paise and upgrading anything higher to the next rupee. Your phone and power bills bristle with decimal points but you can bet that BESCOM and BSNL will turn 646.80 into 647, and 753.34 into 753, as is right and proper.

But going back to the beginning, the gas man, he doth wreak wonders with decimals, he maketh them to jump through hoops. If you look at your bill you will observe that what you pay for your cylinder (which contains 14.2 kg of LPG, by the way) is a basic amount of Rs 415.39, while VAT and so on take the total to Rs 419.96. Shouldn’t you be paying 420, then? If you believe that you’re living on the wrong planet. The figure itself should alert you: 420, cheating case appa! The gas man awards himself Rs 20, and in more upmarket areas, Rs 30. How did you end up paying such a monstrous tip? Let me explain, step by step: In the distant past we used to round off the cost to the nearest multiple of ten: for example, 204.22 would become 210, a roughly six-rupee tip. Inflation drove up not only gas prices but also the tip, to a minimum of Rs 10. Now, if the bill came to, let’s say 337, it proved inconvenient for both you and the gas man, for neither would have the exact change for 347 at hand. Hence you paid Rs 350. A tip of Rs 15 or thereabouts quickly became the new standard. All clear so far? Now look at the latest gas price: Rs 420, for which you are expected to shell out 435, but that five is a problem, right? So it’s rounded off to 440. Q.E.D.

Fortunately, even the most beady-eyed company hesitates to imitate the gas man when dealing with decimals. On the whole, though, the losing party in the decimal game is generally the same person: you.

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