Branded pads retail range Rupees 10-25 per pad - some variation in capacity. So the contemporary ratio ranges from 4:1 to 10:1. So 16:2.5 is good estimate even for contemporary comparison!
@pja you are hereby awarded 1 Fermi (see recent link on the topic of Fermi estimates).
The saving is significant because one can also buy shampoo in sachets that cost Rs.5, so the savings expand access to a range of basic hygiene products.