model 7 marks scored in examinations Practice Questions Answers Test with Solutions & More Shortcuts

Answer: (d)

Number of students passed in first year = 75

Number of students passed in second year

= ${60 × 75}/100 = 45$

Total number of passed students = 75+45=120

Total number of appeared students =175

∴ Required percentage

= $120/175 × 100 = 68{4}/7%$

Answer: (d)

The percentage of students who pass in one or two or both subjects

= 60 + 70 – 40 = 90

Percentage of failed students = 100 – 90 = 10%

Answer: (c)

Let the maximum marks be x.

According to the question,

35% of x = 200 +10 ⇒ ${35x}/100 = 210$

x = ${210 × 100}/35 = 600$

Using Rule 24,

a = 35%, b = 200, c = 10

Maximum Marks = ${100 × (b + c)}/a$

= ${100(200 + 10)}/35$ = 600 Marks

Answer: (d)

Let the full marks in that examination were x.

According to the question,

${30x}/100 + 5 = {40x}/100 - 10$

${4x}/10 - {3x}/10 = 10 + 5$

$x/10 = 15$ ∴ x = 150

Minimum pass marks

$30/100 × 150 + 5 = 50$

Using Rule 22,

m = 30%, n = 40%, p = 5, q = 10.

Maximum marks = $100/{(n - m)} × (p + q)$

= $100/{(40 - 30)} × (5 + 10) = 150$

Minimum passing marks = $150 × 30/100 + 5$

= 45 + 5 = 50

Answer: (c)

Total number of students = 640 + 360 = 1000

Number of successful boys = 60% of 640 = 384

Number of successful girls = 80% of 360 = 288

Total number of successful students = 384 + 288 = 672

Number of unsuccessful students = 1000 – 672 = 328

Required percentage = ${328 × 100}/1000 = 32.8%$

Using Rule 25,

B = 640, G = 360, b = 60%, g = 80%

Percentage of passed students = $({Bb + Gg}/{B + G})%$

= ${640 × 60 + 360 × 80}/{640 + 360}$

= ${38400 + 28800}/1000 = 67200/1000 = 67.2%$

% of failed students = 100 – 67.2% = 32.8%