ALL MRIDANGAM STUDENTS

[unni]

hi my name is Unni. i am a rising mridangam student. there is one aspect of the mridangam i just dont seem to understand...the math behind playing the mridangam. if there are 10 aksharams....such as in this lesson i learned

Na Thin Thin Na
NaKa Thin Thin Na
Kitathaka Thin Thin Na
Tha LanGu Thakathimi Nakathari Kitathaka

Na Thin Thin Na
Tha LanGu Thakathimi Nakathari Kitathaka
NaKa Thin Thin Na
Tha LanGu Thakathimi Nakathari Kitathaka

Tha LanGu Thom Tha Tham
Tha LanGu Thakathimi Nakathari Kitathaka
Tha LanGu Thom Tha Tham
Tha LanGu Thakathimi Nakathari Kitathaka

my teacher says it's 3 1/2 + 3 1/2 + 3 1/2..........all i get from that is 10 1/2..what does that mean? where does he get 3 1/2 from and whats with the addition? can someone help me?