https://simpleedulife.com/an-egg-seller-sells-his-eggs-only-in-the-packs-of-3-eggs-6-eggs-9-eggs-12-eggs-etc-but-the-rate-is-not-necessarily-uniform-one-day-raju-purchased-at-the-rate-of-3-eggs-for-a-rupee-and-the-next-h/