Question : In an examination, the original average mark was found to be 50. To deduct marks for computational errors, the marks of 100 candidates were changed from 90 to 60 each, and the new average of marks became 45. What was the total number of candidates who appeared in the examination?

Option 1: 600

Option 2: 300

Option 3: 200

Option 4: 150

Question : The average of 45 numbers was found to be 39. Later on, it was detected that the number 65 was misread as 56. Find the correct average of the given numbers.

Option 1: 39.2

Option 2: 37.2

Option 3: 38.2

Option 4: 36.2

Question : The average mark obtained by 150 students in an examination is 40. If the average marks of passed students are 60 and those of failed students are 20, what is the number of students who passed the examination?

Option 1: 25

Option 2: 50

Option 3: 75

Option 4: 100

Question : The ratio of the number of boys to girls in a village is 3 : 2. If 30% of boys and 70% of girls appeared in an examination, the ratio of the number of villagers who appeared in the examination to that not appeared in the same examination is:

Option 1: 9 : 14

Option 2: 23 : 27

Option 3: 1 : 1

Option 4: 27 : 23

Question : The total number of candidates who appeared and qualified in a competitive examination from different cities is given in the following bar graph. Study the bar graph carefully and answer the following question.

What is the difference between the average number of appeared candidates and the average number of qualified candidates in the exam from all the cities?

Option 1: 525

Option 2: 550

Option 3: 650

Option 4: 625

Question : The average mark obtained by 180 students in an examination is 50. If the average mark of passed students is 80 and that of the failed students is 40, then what is the number of students who failed the examination?

Option 1: 90

Option 2: 135

Option 3: 100

Option 4: 45