Selling price of 15 shirts = Rs 2340
The loss suffered by the shopkeeper on selling 15 shirts = Rs 60
We know that
Loss = Cost price – Selling price
⇒ Cost price = Loss + Selling price
= Rs 60 + Rs 2340
= Rs 2400
So, cost price of 15 shirts = Rs 2400
Cost price of 1 shirt
Hence, cost price of each shirt = Rs 160