Discount to Saral =
20+25−10020×25​=40% Discount to Himanshu =
=40+40−10040×40​=64% Let a, b, c be the number of units sold at 20%, 40% and 64% respectively.
⇒100a×20​+b×40100+c×64100=(a+b+c)50100⇒507c​−10b​−103a​=0⇒7c−5b−15a=0So ‘c’ has to be a multiple of 5.
Values of a, b, c satisfying the equation are (2,1,5); (1,4, 5); (4, 2, 10); (3, 5, 10); (2, 8, 10).
Hence the possible values for x are 8, 10, 16, 18 and 20.