Treatment of cash deposit in joint bank account

During 2014 my grandma sold gold jewellery worth 150000 for cash (no proof or any sort of sales bill is available in this regards) and she deposit this cash in the joint bank account where i am the primary holder and my grandma is second holder.The very next day i invest Rs.110000 in mutual fund in her name and remaining 40000 in my name (both different folios) but through the same savings account.So how can i treat this Rs. 150000 can the full amount be shown as gift to me from my grandmother but the question is i reinvested this money in her name in mutual fund (110000) or only 40000 which is invest in my name can be shown as the gift then what about the 110000 how it would be treated in income tax.