How rare is a supernumerary rainbow...?

Question

i.e. how many could the average person expect to see in their lifetime?

Answer 1

I've seen several but I was also a weather observer at ome time too...

Answer 2

I have a photograph of a double rainbow taken when I was a teenager. It was so long ago that it is in black & white !

Answer 3

It would depend very much where they live or even on their occupation.

Those who live and work near big waterfalls like Niagara can see rainbows any time the sun shines. Those who work at sea, or fly for a living, see rainbows almost every sunny and showery day, too. City dwellers and workers don't see very many, and miners and other underground workers may see none at all.