On the eve of Gandhi Jayanti a saree is sold for Rs 720 after allowing 20% discount.

Given,

SP of the saree $=$ Rs. 720

Discount on the saree $=20 \%$

We know, Discount $\%=\frac{\text { Discount }}{\text { MP }} \times 100$

Or, Discount $=\frac{\text { Discount } \% \times \text { MP }}{100}$

Let the MP of the saree be Rs. $x$

Therefore, Discount $=\frac{20}{100} x=$ Rs. $0.02 x$

Since S.P $=$ MP $-D$ iscount,

$720=x-0.20 x$

$720=0.80 x$

$x=\frac{720}{0.80}$

$=$ Rs. 900

Thus, the MP of the saree is Rs. 900 .