Manakanakku

Manakanakku (English: "Mental math") is a 1986 Indian Tamil-language drama film directed by R. C. Sakthi, starring Vijayakanth, Sarath Babu, Rajesh, Ambika and Radha in the lead roles. Kamal Haasan acted in a guest appearance. 
This was the only film where both Ambika and Radha voiced their characters themselves and the only film where Kamal Haasan and Vijayakanth appeared on screen together.