The money that hasn't been spent holds infinite possibilities, while the money that has been spent only has one possibility: it has been transformed into material things that accompany you. Otherwise, it's just a string of numbers.
Last year. Now it's 2025. In fact, there isn't much of a story in just a few days.
In the morning, my wife was making pancakes, but the gas ran out, so we couldn't light the stove.
Then we put the frozen pancakes in the oven, and they tasted pretty good.
It's not the kind of gas meter that can be recharged wirelessly. I went to find a recharge card, put it in my pocket, and after finishing my tasks, I had to find time to go to the clinic to recharge.
I hurried back at noon, took a card to recharge 100 yuan, but it was actually around 99.6 on the card. However, the gas meter requires whole numbers, so I prepared to insert the card into the gas meter. I moved the rice box aside. I inserted the card, and there was a sound of gears moving. I used my phone's LED to check; the gas meter's battery was low. I tried to light it, but there was no response, it didn't ignite. I was using rechargeable batteries labeled "love husband" and "love wife," and I estimated that with winter approaching and having used them for more than half a year, the battery was low. The voltage was indeed low, measuring around 1V. A full charge is generally around 1.45V. The gas stove's battery is 1.2V, which is considered relatively high.
I planned to replace the gas meter with the gas stove's battery. The gas stove's battery is not a type 1 battery; I was using three type 5 batteries converted into one type 1 battery. I used rechargeable ones when possible; generally, charging three type 5 batteries three times would recoup the cost compared to directly buying type 1 batteries.
The four 1.2V batteries still couldn't start. I used that universal charger to charge the four batteries together; at a speed of 500mAh, it would take 3-4 hours. My wife also came back and asked me to buy the old 1 yuan for four type 5 batteries from the Shuanglu brand. I didn't know the current price. I was also resistant, feeling it was a waste of money.
My approach was to go to the supermarket to buy a boxed meal for 8.9 yuan for my wife, and I bought four steamed buns for 1.99 yuan, then came back to eat instant noodles.
My wife said that to save 1.2 yuan, she spent more money to buy the boxed meal and buns, which wasn't cost-effective.
I felt it was worth it.
What kind of calculations does everyone use?