The number of questions answered correctly = 90.
<h3>What is a system of linear equations?</h3>
- A system of linear equations is a set of two or more linear equations.
- Linear equations refer to the equations that involve two or more variables in the form of "ax + b".
Now,
Given:
- Total number of questions = 200
- Marks for correct answer = 4
- Marks for incorrect answer = -1
- Total marks = 250
To find : Number of correct answers = ?
Finding:
Now, assuming that the student attempted and answered all the questions,
- Let the number of questions correctly answered be x and incorrectly answered be y.
Then,
- x + y = 200 (For number of questions) (eqn 1)
- and 4x - y = 250 (For the marks scored) (eqn 2)
Solving the system of linear equations:
For eqn 2, we get that y = 4x - 250
Substituting in eqn 1, we get:
=> x + 4x - 250 = 200
=> 5x = 250 + 200 = 450
=> x = 90
That is, the number of questions answered correctly = 90, the incorrect answers = 200 - 90 = 110.
To learn more about system of linear equations, refer to the link: brainly.com/question/2226590
#SPJ4
First, you would multiply: -13 = 70m - 2m. Then, you subtract the like terms, which would be 70m - 2m: -13 = 68m. You are looking for what m is, so you would divide 68 on both sides: m = - 13 / 68. In math, people would usually like fractions more than decimals, but if you are looking for the decimal number, it would be m ≈ - 0.19.
Answer:
- the total installment is $936
- the carrying charges are $186
- the monthly rate to buy the items are 19.23 or 20 months
Step-by-step explanation:
$39 for 24 months comes to ...
$39 × 24 = $936
The "carrying charges" are the difference between the cash price and the installment price:
$936 -750 = $186
Saving at the rate of $39 per month, it would take ...
$750/$39 = 19.23 months
about 20 months to save up the cash price.
Often, such savings would come from a once-a-month paycheck, so it would take more than 19 such paychecks to save the required amount.
hope it will help :)
I'd say B. but that's only because I divided the number of times he flipped the coin by the number of sides it has, 2, and came up with 246. The closest number on here to that is 231 or B. I hope I helped.
