The cost of painting the top surface of a triangular board at 80 paise per sq.mt is Rs 176.40. If the height of the board measures 24.5, find its base.

Dear Student,
Rate of painting is .8 Rs per sqm 
then total area =176.4/.8 
=220.5 m2 
now 1/2 x b x h = 220.5 
and h = 24.5 m 
then b= 220.5/(1/2 x 24.5 ) 
= 220.5/12.25 
= 18 m

Regards,