model 7 marks scored in examinations Section-Wise Topic Notes With Detailed Explanation And Example Questions

Answer: (a)

Total candidates = 1000 + 800 = 1800

The candidates who are passed

= $1000 × 60/100 + 800 × 50/100$

= 600 + 400 = 1000

The number of candidates who failed = 1800 – 1000 = 800

Required percent = $800/1800 × 100 = 44.4%$

Using Rule 25,

Percentage of passed students = $({B.b + G.g}/{B + G})%$

= ${1000 × 60 + 800 × 50}/{1000 + 800}$

= ${60000 + 40000}/1800$

= $100000/1800 = 500/9 = 55.5$

Percentage of failed students = 100 – 55.5 = 44.4%

Answer: (a)

Let the total marks be x.

According to the question,

25% of x + 40 = 33% of x

(33 – 25)% of x = 40

8% of x = 40

x = ${40 × 100}/8$ = 500

Answer: (b)

Let maximum marks be x, then,

${36 × x}/100 = 113 + 85 = 198$

$x = {198 × 100}/36 = 550$

Using Rule 24,

a = 36%, b = 113, c = 85

Maximum marks = ${(b + c)}/a × 100$

= ${(113 + 85)}/36 × 100$

= $198/36 × 100$ = 550

Answer: (b)

Let total number of students = 100

27 students speak none of the two languages.

It means only 73 students speak either Hindi or English or both.

Let x students speak both languages.

∴ 73 = 70 – x + x + 65 – x

x = 70 + 65 – 73 = 62%