Question

A billfold holds one-dollar, five-dollar, and ten-dollar bills and has a value of $210. There are 50 bills total where the number of one-dollar bills is one less than twice the number of five-dollar bills. How many of each bill are there? Write your answer as an ordered triple in the form (# of one dollar bills, # of five dollar bills, # of ten dollar bills).

Answer 1

Answer:

25 of one dollar bills, 13 of five dollar bills, 12 of ten dollar bills.

Step-by-step explanation:

You can write the following equations:

x+y+z=50 (1)

x+5y+10z= 210 (2)

x= 2y-1 (3)

x= number of one dollar bills

y= number of five dollar bills

z= number of ten dollar bills

Then, you can replace (3) in (1) and (2):

2y-1+y+z= 50

3y+z=51

2y-1+5y+10z= 210

7y+10z=211

From that, you will get the following equations:

3y+z=51 (4)

7y+10z=211 (5)

Now, you have to isolate z in (4) and replace it in (5):

z= 51-3y

7y+10(51-3y)=211

7y+510-30y=211

-23y=-299

y= 13

Then, replace the value of y in z= 51-3y:

z=51-3(13)= 51-39= 12

After this, you can replace the value of y in (3):

x=2(13)-1= 26-1= 25

According to this, the answer is that there are 25 of one dollar bills, 13 of five dollar bills, 12 of ten dollar bills.