On her way to a concert, Hermione stopped at a restaurant for dinner. In her purse, she had 12 bills worth a total of $40. She had only $1 bills and $5 bills. How many $5 bills did Hermione have in her purse?

Question

1
2
5
7

Answer 1

Let $x$ be the number of $1 bills and $y$ be the number of $5 bills. We are given two equations based on the information provided:

1. The total number of bills: $$x+y=12$$

2. The total value of the bills: $$1x+5y=40$$

Now we can solve these equations step by step.

From the first equation, we can express $x$ in terms of $y$: $$x=12-y$$

Next, we substitute $x$ in the second equation: $$1(12-y)+5y=40$$ This simplifies to: $$12-y+5y=40$$ $$12+4y=40$$ Subtract 12 from both sides: $$4y=28$$ Now divide by 4: $$y=7$$

Now that we have $y$, we can find $x$: $$x=12-y=12-7=5$$

Thus, Hermione has:

• 5 $1 bills
• 7 $5 bills

The answer to how many $5 bills Hermione had is: $$\boxed{{\displaystyle 7}}$$