Having problem in displaying number!

A1=25.25 (outcome of some calculations, formatted as
number with two decimal places)

In A10, I am trying to display

Please pay a sum of Rs. 25.25 only

I am using the formula A10="Please pay a sum of Rs. "&A1&" only"

Problem is coming with amounts like 25.00 or 25.50, the cell displays
for 25.50 ---- Please pay a sum of Rs. 25.5 only (what I want is 25.50)
for 25.00----- Please pay a sum of Rs. 25 only (what I want is 25.00)

separating Integar and Fraction part is not of help. Using =right(a1,1) also
does not work.

Help will be appreciated, preferably with use of functions only!