Question 811464: I need to show the work for the following question:
A bank teller has 54 $5 and $20 bills in her cash drawer. The value of the bills is $780. How many $5 are there?
I know the answer is 20 $5 and 34 $20, but I am not sure how to show the work. Here is what I have so far:
The approach to solve problems with algebra is usually quite different. Word problems are solved by separating information from the problems into two equal groups, one for each side of an equation. Examine this problem.
A bank teller has 54 $5 and $20 bills in her cash drawer. The value of the bills is $780. How many $5 are there?
We know that the sum of $5 and $20 is equal to the total amount of money. An unknown number or value is represented by a letter. The total number of $5 bills is unknown, so we will represent that amount with x. When the value that a particular variable will represent is determined, it is defined by writing a statement like,
Let x = Number of $5
Once again, the sum of $5 and $20 is equal to the total amount of money ($780). This can be used to translate the problem into an equation, like the following:
5 + 20 = x
The next step is to solve this equation.
Now solve the equation which was created in the last step.
Let x = Number of $5
Initial Equation 5 + 20 = x
After combining like terms 25 = x
The answer is then rewritten as a sentence.
There are 25 Total number of $5.
By using simple arithmetic, this problem probably could have been solved faster without setting up an algebra equation. But, knowing how to use an equation for this problem builds awareness of concepts which are useful, and sometimes critical to solving much harder problems. One such problem will be presented in the next example.
Answer by richwmiller(17219)   (Show Source):
You can put this solution on YOUR website! Most of what you said for the problem is wrong
let f= number of $5 bills
let t= number of $20 bills
f+t=54,
5f+20t=780
f = 20, t = 34
There are 20 $5 bills and 34 twenty dollar bills
check
f=20 and t=34
5*20=100
34*20=680
680+100=780
ok
|
|
|
