Question

Century Go...

Answer 1

6 bills in the deposit were $10 bills.

Step-by-step explanation:

The total number of bills he gave the teller = 24 bills

x + y = 24 ------------(1)

Let,

x be the number of $5 bills.

y be the number of $10 bills.

The total bank deposit made using $5 and $10 bills are $150.

He deposits $5 bills and $10 bills. So, the equation can be framed as :

5x + 10y = 150 --------(2)

The question is asked for how many $10 bills were in the deposit,

Here 'y' is the number of $10 bills.

To solve for y value :

The eq(1) must be multiplied by 5 and subtract eq(2) from eq(1),

 5x + 5y = 120

-(5x + 10y = 150)

 -5y = -30      

⇒ y = 30/5

⇒ y = 6

Therefore, there were 6 bills in the deposit that are $10 bills.