Isinya Eggs, 15 Pieces is currently tracked at KSh 330 at Naivas - working out to KSh 22 per egg.
Compare that to a 6-pack of Jandee Eggs at KSh 140, or about KSh 23.30 per egg - the larger 15-piece pack is marginally cheaper per egg, as is typical with bulk packaging. The difference here is small (about 6%), so it mostly matters if you're buying in volume regularly rather than as a one-off top-up.
Bigger pack, faster use
The per-egg saving on the 15-pack only pays off if you'll use them before they go off - for a small household that doesn't cook with eggs daily, the smaller 6-pack at a marginally higher per-unit price may still be the more practical buy.