SOLUTION: "A bank teller has 35 bills in $5, $10, and $20 denominations. The total value from these bills is $370. The total number of $10 bills and $20 bills is 7 more than the number of $5

Algebra ->  Coordinate Systems and Linear Equations  -> Lessons -> SOLUTION: "A bank teller has 35 bills in $5, $10, and $20 denominations. The total value from these bills is $370. The total number of $10 bills and $20 bills is 7 more than the number of $5      Log On


   

Question 856603: "A bank teller has 35 bills in $5, $10, and $20 denominations. The total value from these bills is $370. The total number of $10 bills and $20 bills is 7 more than the number of $5. How many bills of each denomination does the teller have?"
What I have done:
x+y+z=35
5x+10y+20z=370
y+z+7=x
Then I keep getting fractions/decimals which is not correct
Found 2 solutions by Fombitz, ewatrrr:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Your third equation is incorrect.
y%2Bz=7%2Bx
"Is" is usually the tip-off word that means equals.
Try it like this and see what you get.
If you need help, please repost.

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

The total number of $10 bills and $20 bills is 7 more than the number of $5

 y + z = x + 7

-7 + (y +z) = x

35 - (y +z) = x

  28 = 2x

  14 = x, number of $5 bills

(y + z) = 21 , y = +21-z

5x+10y+20z=370   |Yes! Now substitute

 $90 + $10(21-z) + $20z = $370

  $90 + $210 + $10z = $370

           $10z = 70 

             z = 7,  number of $20 bills. There are 14 $10 bills

CHECKING our answer***

 $90 + $140 + $140 = $$370

Wish You the Best in your Studies.