Percentage - Aptitude MCQ Questions and Solutions with Explanations

Answer: Option C

Let the number of persons eligible to vote be x
Then, votes who voted for A = 30% of x
Votes who voted for B = 60% of (70% of x)
= $$\left( {\frac{{60}}{{100}} \times \frac{{70}}{{100}} \times 100} \right)$$   % of x
= 42% of x
Voters who did not vote = [100 - (30 + 42)]% of x = 28% of x
∴ 30% of x - 28% of x = 1200
⇒ 2% of x = 1200
⇒ x = $$\left( {\frac{{1200 × 100}}{{2}}} \right)$$
⇒ x = 60000

Answer: Option B

Let x% of x = 10% of y
Then,
$$\eqalign{ & \Rightarrow \frac{x}{{100}} \times x = \frac{{10}}{{100}} \times y \cr & \Rightarrow y = \frac{{{x^2}}}{{100}} \times 10 \cr & \Rightarrow y = \frac{{{x^2}}}{{10}} \cr} $$

Answer: Option A

Let the total number of employees be x
Then,
(100 - 50)% of (100 - 40)% of x = 180
50% of 60% of x = 180
$$\eqalign{ & \Rightarrow \left( {\frac{{50}}{{100}} \times \frac{{60}}{{100}} \times x} \right) = 180 \cr & \Rightarrow x = \left( {\frac{{180 \times 10}}{3}} \right) \cr & \Rightarrow x = 600 \cr} $$
∴ Number of graduate employees :
$$=$$ 50% of 60% of x
$$\eqalign{ & = \left( {\frac{{50}}{{100}} \times \frac{{60}}{{100}} \times 600} \right) \cr & = 180 \cr} $$

Answer: Option C

$$\eqalign{ & A = \frac{{120}}{{100}}B, \cr & B = \frac{{120}}{{100}}C\, \& \cr & C = \frac{{85}}{{100}}D \cr & \therefore B = \frac{5}{6}A \cr & C = \frac{5}{6}B\, \& \cr & D = \frac{{20}}{{17}}C \cr & B = \frac{5}{6} \times 576 = 480 \cr & C = \frac{5}{6} \times 480 = 400 \cr & D = \frac{{20}}{{17}} \times 400 = \frac{{8000}}{{17}} \cr} $$
So, required percentage :
$$\eqalign{ & = \left( {\frac{{8000}}{{17}} \times \frac{1}{{800}} \times 100} \right)\% \cr & = 58.82\% \cr} $$

Answer: Option C

Let the original price = Rs. 100
New price = Rs. 75
Increase on 75 = 25
Increase on 100 :
$$\eqalign{ & = \left( {\frac{{25}}{{75}} \times 100} \right)\% \cr & = \frac{{100}}{3}\% \cr & = 33\frac{1}{3}\% \cr} $$