Mark B. answered • 11/25/17
Tutor
New to Wyzant
PhD Candidate in Psychology: Experienced Math, Statistics, Tutor
Good Morning, Astrid,
This is a proportional problem allowing you to set up a proportional equation.
You are given some information - in fact three of the variables (250 dollars for 4250 pesos exchange rate; and how much in pesos priya bought the sweater for; 510 pesos.
Therefore:
Dollars/Pesos = Dollars/Pesos
Given:
250/4250 = x (unknown dollar amount)/510 pesos
Please note: When setting up a proportional equation you MUST make sure you have same units or things on numerator and denominator on BOTH sides of the equation, okay? In our problem we have the dollars on the numerators and pesos in the denominators, right??
Now we are left with the following equation:
250/4250 = x/510
Since an equal is between the two proportional values you can now cross multiply the numerator from the fraction on the left with the denominator of the fraction on the right, and then the denominator of the fraction on the left with the numerator of the fraction on the right. Doing so leaves you with the following, okay?
250(510) = 4250x
127,500 = 4250x
Remember, whatever you do to one side of an equation you MUST do on the other, correct? Great.
Now, you need to divide 4250 from both sides of the equation to leave x to itself.
Doing so leaves you with the following:
x = 30
That means according to this proportional equation Priya actually paid $30.00 on the sweater.
Astrid, could you have used a short-cut? Yes. But the problem I have giving you the answer using that short-cut, is that I am not providing you with the necessary tools you will need for later levels of math or Algebra. This is a tool you can place in your toolbox to assist you down the road when you get to more complex problems, okay?
Now, you can also check your work by setting up a proportion by asking if Priya's family gave one dollar how many pesos would they get in return. That proportional equation looks like this:
250/4250 = 1/x Where 250 dollars is the amount given for exchange, 4250 is the amount of pesos received, and 1 is the dollar amount you are giving to determine how many pesos per dollar it works out to, correct? Do you see it?
Doing this we arrive at 250x = 4250 through cross-multiplying
x = 17 when we divide 250 from each side of the equation.
That means 1 dollar is equal to 17 pesos, correct?
Since Priya family's exchange rate is 1 dollar for 17 pesos, now all you need do to check your work is to divide 17 pesos into 510 to determine the dollar amount, correct?
When you do this, you find the answer is EXACTLY the same: 30
I have given everything you need now for a table.
Please let me know through follow-up that you fully understand the way I reached your answer. All you need to do is to post a follow up statement as a question.
Wishing you a great weekend!
This is a proportional problem allowing you to set up a proportional equation.
You are given some information - in fact three of the variables (250 dollars for 4250 pesos exchange rate; and how much in pesos priya bought the sweater for; 510 pesos.
Therefore:
Dollars/Pesos = Dollars/Pesos
Given:
250/4250 = x (unknown dollar amount)/510 pesos
Please note: When setting up a proportional equation you MUST make sure you have same units or things on numerator and denominator on BOTH sides of the equation, okay? In our problem we have the dollars on the numerators and pesos in the denominators, right??
Now we are left with the following equation:
250/4250 = x/510
Since an equal is between the two proportional values you can now cross multiply the numerator from the fraction on the left with the denominator of the fraction on the right, and then the denominator of the fraction on the left with the numerator of the fraction on the right. Doing so leaves you with the following, okay?
250(510) = 4250x
127,500 = 4250x
Remember, whatever you do to one side of an equation you MUST do on the other, correct? Great.
Now, you need to divide 4250 from both sides of the equation to leave x to itself.
Doing so leaves you with the following:
x = 30
That means according to this proportional equation Priya actually paid $30.00 on the sweater.
Astrid, could you have used a short-cut? Yes. But the problem I have giving you the answer using that short-cut, is that I am not providing you with the necessary tools you will need for later levels of math or Algebra. This is a tool you can place in your toolbox to assist you down the road when you get to more complex problems, okay?
Now, you can also check your work by setting up a proportion by asking if Priya's family gave one dollar how many pesos would they get in return. That proportional equation looks like this:
250/4250 = 1/x Where 250 dollars is the amount given for exchange, 4250 is the amount of pesos received, and 1 is the dollar amount you are giving to determine how many pesos per dollar it works out to, correct? Do you see it?
Doing this we arrive at 250x = 4250 through cross-multiplying
x = 17 when we divide 250 from each side of the equation.
That means 1 dollar is equal to 17 pesos, correct?
Since Priya family's exchange rate is 1 dollar for 17 pesos, now all you need do to check your work is to divide 17 pesos into 510 to determine the dollar amount, correct?
When you do this, you find the answer is EXACTLY the same: 30
I have given everything you need now for a table.
Please let me know through follow-up that you fully understand the way I reached your answer. All you need to do is to post a follow up statement as a question.
Wishing you a great weekend!