SOLUTION: A bag contain 100,50,and 40 currency note.the 100 and 50 currency note are in 2:5 ratio and the 50 and 10 currency note are in the ratio 4:9.if the total amount is 11250. Find the

I will re-phrase the condition in this way:


    100- and 50- currency notes are in the ratio 2:5,  which is the same as 8:20,

    while 50- and 10- currency notes are in the ratio 4:9, which is the same as 20:45.



It means that for every 20  50-currency bills, there are 8 100-currency bills and 45 10-currency bills.


Thus you can group the notes, placing 20 50-currency bills, 8 100-currency bills and 45 40-currency bills in each group.


Then each group is worth  20*50 + 8*100 + 45*10 = 2250 currency units,

and the number of such groups is   = 5.


From this point, only one step is needed to get the 


ANSWER.  There are 5*20 = 100   50- currency bills;

                   5*8  =  40   100- currency bills, and

                   5*45 = 225   10- currency bills.