Answer:
Option (3)
Step-by-step explanation:
From the picture attached,
Bar graph sketched shows the grades earned by the students in an exam.
Number of students who achieved the grade A = 17
Number of students who achieved grade B = 14
Number of students with grade C = 5
Number of students with grade D = 9
Total students who took the exam = 17 + 14 + 5 + 9 = 45
Option (1)
"
of the students earned a C"
Fraction of students who earned C = ![\frac{\text{Students who earned C}}{\text{Total students}}](https://tex.z-dn.net/?f=%5Cfrac%7B%5Ctext%7BStudents%20who%20earned%20C%7D%7D%7B%5Ctext%7BTotal%20students%7D%7D)
= ![\frac{5}{45}](https://tex.z-dn.net/?f=%5Cfrac%7B5%7D%7B45%7D)
= ![\frac{1}{9}](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B9%7D)
Therefore, this option is incorrect.
Option (2)
"3% more students earned an A then B"
Percentage of students who earned A = ![\frac{\text{Students got A}}{\text{Total students who took the exam}}\times 100](https://tex.z-dn.net/?f=%5Cfrac%7B%5Ctext%7BStudents%20got%20A%7D%7D%7B%5Ctext%7BTotal%20students%20who%20took%20the%20exam%7D%7D%5Ctimes%20100)
= ![\frac{17}{45}\times 100](https://tex.z-dn.net/?f=%5Cfrac%7B17%7D%7B45%7D%5Ctimes%20100)
= 37.78%
Percentage of students who earned B = ![\frac{\text{Students got B}}{\text{Total students who took the exam}}\times 100](https://tex.z-dn.net/?f=%5Cfrac%7B%5Ctext%7BStudents%20got%20B%7D%7D%7B%5Ctext%7BTotal%20students%20who%20took%20the%20exam%7D%7D%5Ctimes%20100)
= ![\frac{14}{45}\times 100](https://tex.z-dn.net/?f=%5Cfrac%7B14%7D%7B45%7D%5Ctimes%20100)
= 31.11%
Difference in percentage = 37.78 - 31.11
= 6.67%
Therefore, this option is not correct.
Option (3)
"20% of the students earned a D"
Percentage of students who earned D = ![\frac{\text{Students got D}}{\text{Total students who took the exam}}\times 100](https://tex.z-dn.net/?f=%5Cfrac%7B%5Ctext%7BStudents%20got%20D%7D%7D%7B%5Ctext%7BTotal%20students%20who%20took%20the%20exam%7D%7D%5Ctimes%20100)
= ![\frac{9}{45}\times 100](https://tex.z-dn.net/?f=%5Cfrac%7B9%7D%7B45%7D%5Ctimes%20100)
= 20%
Option (3) is the correct option.
Option (4)
"
of the class earned a B"
Fraction of class who earned B = ![\frac{\text{Students got B}}{\text{Total students who took the exam}}](https://tex.z-dn.net/?f=%5Cfrac%7B%5Ctext%7BStudents%20got%20B%7D%7D%7B%5Ctext%7BTotal%20students%20who%20took%20the%20exam%7D%7D)
= ![\frac{14}{45}](https://tex.z-dn.net/?f=%5Cfrac%7B14%7D%7B45%7D)
Therefore, Option (4) is not correct.