You go to the store to pick out a watermelon, so what do you do?
Here is my method.
I start thumpin’ the melon with my thumb and index finger or rap it with my knuckles.
If I hear a high pitch sound the watermelon is probably under ripe. Plink
If I hear a low pitch sound or dull thud the watermelon is probably over ripe. Plunk
If I hear a pitch between the two sounds the watermelon is probably ripe. Plank
Try this method and watch the other shoppers make amused faces.
Yes, it works.
Let me know how this method works for you.