IDNLearn.com offers a collaborative platform for sharing and gaining knowledge. Discover comprehensive answers to your questions from our community of knowledgeable experts.
Sagot :
Answer:
80 Questions
Step-by-step explanation:
First 20/32
then 3/4 questions wrong
so let's say he got there were 48 remaining questions
then he would have 36 wrong and and 12 correct
therefore it would be..
20 + 12/32 + 48
32/80
__________________________________________
so let's check the answer
it says he got 40%
so let's do 32/80
= 0.4
to convert it into percentage times by 100
= 0.4 x 100
= 40%
Answer:
There are [tex]80[/tex] questions on this exam.
Step-by-step explanation:
Let [tex]x[/tex] denote the number of questions on this exam in total (including the first [tex]32[/tex] questions.)
There would be [tex](x - 32)[/tex] questions after the first [tex]32[/tex].
Since the student got three-quarters of these wrong, only one-quarter ([tex]1 - (3/4) = (1/4)[/tex]) of these [tex](x - 32)[/tex] questions are correct. That would be another [tex](1/4) \cdot (x - 32)[/tex] right answers.
In total, the number of questions that the student got correct would be:
[tex]\begin{aligned} & 20 + \frac{1}{4} \cdot (x - 32) \\ =\; & 20 + \frac{x}{4} - 8 \\ =\; & 12 + \frac{x}{4}\end{aligned}[/tex].
On the other hand, it is given that the student got [tex]40\%[/tex] of the [tex]x[/tex] questions right. Hence, the number of correct answers may also be expressed as:
[tex]\begin{aligned} & (40\%) \, x\\ =\; & \frac{2\, x}{5} \end{aligned}[/tex].
Both expressions give the number of correct answers. Equate the two expressions and solve for [tex]x[/tex]:
[tex]\displaystyle 12 + \frac{x}{4} = \frac{2\, x}{5}[/tex].
[tex]\displaystyle \left(\frac{2}{5} - \frac{1}{4}\right)\, x = 12[/tex].
[tex]\displaystyle \frac{8 - 5}{20}\, x = 12[/tex].
[tex]\displaystyle \frac{3}{20}\, x = 12[/tex].
[tex]\begin{aligned} x &= 12 \times \frac{20}{3} \\ &= 80\end{aligned}[/tex].
In other words, there are [tex]80[/tex] questions on this exam in total.
We appreciate your contributions to this forum. Don't forget to check back for the latest answers. Keep asking, answering, and sharing useful information. Thank you for choosing IDNLearn.com. We’re committed to providing accurate answers, so visit us again soon.
