Percentage Problems and Solutions

• 29. 88% of 370 + 24% of 210 - x = 118

  1. 150
  2. 250
  3. 158
  4. 258

  Answer :

  Option D

• 30. Raman's salary was decreased by 50% and subsequently increased by 50%. How much percent does he loss.

  1. 75
  2. 65
  3. 45
  4. 25

  Answer :

  Option D

  Explanation:

  Let the origianl salary = Rs. 100
  
  It will be 150% of (50% of 100)
  = (150/100) * (50/100) * 100 = 75
  
  So New salary is 75, It means his loss is 25%

• 31. If x% of y is 100 and y% of z is 200, then find the relation between x and z.

  1. z = x
  2. 2z = x
  3. z = 2x
  4. None of above

  Answer :

  Option C

  Explanation:

  It is , y% of z = 2(x% of y)
  => yz/100 = 2xy/100
  => z = 2x

• 32. Total number of boys and girls in a school is 150. If the number of boys is x, then girls become x% of the total number of students. The number of boys is

  1. 50
  2. 60
  3. 70
  4. 80

  Answer :

  Option B

  Explanation:

  Clearly,
  x% of 150 = 150 - x [as x is number of boys]
  
  \begin{aligned}
  => x + \frac{x}{100} * 150 = 150 \\
  
  => \frac{5}{2}x = 150 \\
  
  => x = 60 \\
  \end{aligned}

• 33. An inspector rejects 0.08% of the meters as defective, How many meters he examine to reject 2 meteres

  1. 1200
  2. 2400
  3. 1400
  4. 2500

  Answer :

  Option D

  Explanation:

  It means that 0.08% of x = 2
  \begin{aligned}
  => ( \frac{8}{100 \times 100} \times x) = 2 \\
  => x = \frac{2 \times 100 \times 100}{8} \\
  => x = 2500
  \end{aligned}