Percentage - Aptitude MCQ Questions and Solutions with Explanations

Answer: Option D

Number of women = 40% of 200 = 80
Number of men = 200 - 80 = 120
Number of women lectures = $$\frac{1}{5}$$ of 80 = 16
Number of men lectures = 16 × 2 = 32
∴ Required percentage :
$$\eqalign{ & = \left( {\frac{{32}}{{120}} \times 100} \right)\% \cr & = \frac{{80}}{3}\% \cr & = 26\frac{2}{3}\% \approx 27\% \cr} $$

Answer: Option A

Let, his income be = Rs. 100
Saving = Rs. 10
Expenditure = Rs. 90
Increased income = Rs. 120
Increased expenditure = Rs. 110
Increased in expenditure :
$$\eqalign{ & = \frac{{110 - 90}}{{90}} \times 100 \cr & = \frac{{200}}{9} \cr & = 22\frac{2}{9}\% \cr} $$

Answer: Option C

Quantity of alcohol in 10 c.c. solution
= (20% of 6 + 60% of 4) c.c.
= $$\left( {\frac{{20}}{{100}} \times 6 + \frac{{60}}{{100}} \times 4} \right)$$    c.c.
= (1.2 + 2.4) c.c.
= 3.6 c.c.
∴ Required strength :
$$\eqalign{ & = \left( {\frac{{3.6}}{{10}} \times 100} \right)\% \cr & = 36\% \cr} $$

Answer: Option B

Actual price :
$$= Rs. (25 + 2.5)$$
$$= Rs. 27.50$$
∴ Saving :
$$\eqalign{ & = \left( {\frac{{2.50}}{{27.50}} \times 100} \right)\% \cr & = \frac{{100}}{{11}}\% \cr & = 9\frac{1}{{11}}\% \approx 9\% \cr} $$

Answer: Option B

Let the worth of the house be Rs. x
Then,
$$\frac{2}{7}$$% of x = 28000
$$\eqalign{ & \Rightarrow \left( {\frac{2}{7} \times \frac{1}{{100}} \times x} \right) = 2800 \cr & \Rightarrow x = \left( {\frac{{2800 \times 100 \times 7}}{2}} \right) \cr & \Rightarrow x = 980000 \cr} $$