Percentage - Aptitude MCQ Questions and Solutions with Explanations

Answer: Option A

Number of bushes in the beginning :
$$\eqalign{ & = \frac{{26730}}{{\left( {1 + \frac{{10}}{{100}}} \right)\left( {1 + \frac{8}{{100}}} \right)\left( {1 - \frac{{10}}{{100}}} \right)}} \cr & = \left( {26730 \times \frac{{10}}{{11}} \times \frac{{25}}{{27}} \times \frac{{10}}{9}} \right) \cr & = 25000 \cr} $$

Answer: Option C

Let total quantity of original milk = 1000 gm
Milk after first operation = 80% of 1000 = 800 gm
Milk after second operation = 80% of 800 = 640 gm
Milk after third operation = 80% of 640 = 512 gm
∴ Strength of final mixture = 51.2%

Answer: Option C

$$66\frac{2}{3}$$% of Rs. 312/- exceeds Rs. 200 by Rs. $$x$$
According to the question, required difference
$$\eqalign{ & x = {\text{Rs}}{\text{. }}\left( {312 \times \frac{{200}}{3}\% - 200} \right) \cr & x = {\text{Rs}}{\text{. }}\left( {312 \times \frac{{200}}{{3 \times 100}} - 200} \right) \cr & x = {\text{Rs}}{\text{. }}\left( {312 \times \frac{{200}}{{300}} - 200} \right) \cr & x = {\text{Rs}}{\text{. }}\left( {208 - 200} \right) \cr & x = {\text{Rs}}{\text{. 8}} \cr} $$

Answer: Option D

Let 125% of 3060 - 85% of x = 408
Then,
$$\eqalign{ & 85\% {\text{ of }}x = \left( {\frac{{125}}{{100}} \times 3060} \right) - 408 \cr & \Rightarrow \frac{{85}}{{100}}x = 3825 - 408 \cr & \Rightarrow \frac{{17x}}{{20}} = 3417 \cr & \Rightarrow x = \left( {\frac{{3417 \times 20}}{{17}}} \right) \cr & \Rightarrow x = 4020 \cr} $$

Answer: Option D

Let David's annual income be Rs. x and his wife's annual income be Rs. y
Then,
8% of x = 800
⇒ $$\frac{8}{100}$$x = 800
⇒ x = $$\left( {\frac{{800 \times 100}}{{8}}} \right)$$
⇒ x = 10000
And, 8% of y = 840
⇒ $$\frac{8}{100}$$y = 840
⇒ y = $$\left( {\frac{{840 \times 100}}{{8}}} \right)$$
⇒ y = 10500
∴ Required difference :
= [(10500 + 840) - (10000 + 800)]
= Rs. (11340 - 10800)
= Rs. 540