Please my good friend

I received an email on 6th November 2014:

From: nana issa
To: Sao
Sent: Thursday, 6 November 2014 7:09 PM
Subject: Please my good friend,

Please my good friend,
I am the General Audit Manager, Accounts Department in our bank. I have the opportunity of transferring the sum of (US$5.5 million).This fund originally belonged to one of our bank Customer who died in the year 2004.
My request for foreigner to stand as next of kin in this business is because the fact that the customer is a foreigner. Based on the fact that this is a deal, I propose that 40% of this fund for you and 50% for me.10% for the poorest and rest for me I will give more detail of the transfer process as soon as you show your interest in this transaction.Email:mr.issa_nana4@terra.com
Thanks,

This was my reply to him (her?)

To

nana issa

Dear Mr. Issa Nana 3. The email contact that you gave me was for mr.issa nana 4. But I hope that this email will reach you in good health.

I am sorry for your customer who died. But inside, I am a happy that you want to share his money with me.  

I have a small problem regarding your mathematics though:

You said you will give me 40%, 50% for you, 10% for the poorest (you are a noble soul), and the rest for you. According to my calculation, 40%+50%+10% = 100%. So, I am wondering where the money is going to come for ‘the rest’. Please clarify, so that I can give my bank details.

Good Fren