An exam worth 269 points contains 36 questions. some questions are worth 7 points, and the others are worth 8 points. how many 7 point and 8 point questions are on the test?

There are 19 questions worth 7 points.

There are 17 questions worth 8 points.

Step-by-step explanation:

Assign variables:

Let x = number of questions worth 7 points.

Let y = number of questions worth 8 points.

First we deal with the number of questions.

There are 36 questions, so our first equation is:

x + y = 36

Now we deal with the points.

x questions worth 7 points each are worth 7x points.

y questions worth 8 points each are worth 8y points.

The total worth of all the questions is 7x + 8y.

The total worth of the exam is 269, so our second equation is

7x + 8y = 269

We have a system of 2 equations in 2 variables.

x + y = 36

7x + 8y = 269

Let's use the substitution method to solve the system of equations.

Solve the first equation for x.

x + y = 36

x = 36 - y

Substitute 36 - y in for x in the second equation.

7x + 8y = 269

7(36 - y) + 8y = 269

Distribute the 7.

252 - 7y + 8y = 269

Combine like terms.

252 + y = 269

Subtract 252 from both sides.

y = 17

There are 17 questions worth 8 points.

x + y = 36

x + 17 = 36

x = 19

There are 19 questions worth 7 points.

Check:

What does 19 questions at 7 points each and 17 questions at 8 points each add to?

19 * 7 + 17 * 8 = 133 + 136 = 269

The points add to 269, so our answer is correct.

pay attention in your classes and concentrate the best thing you can do to raise your test scores is to pay attention when you're supposed to be learning the material: in class!

take good notes.

do your homework.

use mnemonics and other tricks.

do practice tests.

note: the best i know.

yes the total will be same because in both of them the expression.is rearranged but their sign remains the same hence it hss just been shuffled