Everytime that I do my grocery, I usually follow these calculations. There are times wherein I just buy the sachet part as I rarely use some items. Magic Sarap is a good example as I buy one or two sachets only. If I buy a huge packet the rest either got thrown away or unusable anymore.
But definitely it is a good tip! Calculate always to see where we can save.
Doing calculations before purchasing is a very bright idea. Through this, we will know how much we can save. Choosing the type of packaging is also another way. Like in magic sarap we can choose resealable packaging to make it safe from dust and moisture and save the surplus for future use.