Subject: General Aptitude · Chapter: Area · Exam: · Marks: · Difficulty:
A courtyard is 25m long and 16m broad is to be paved with bricks of dimensions 20cm by 10cm. What is the total number of bricks required? [IBPS-RRB Office Assistant (Online) Exam, 2015]
(a)16000
(b)18000
(c)20000
(d)22000
Answer
Answer (as printed): C
Explanation
Given length and breadth of courtyard is 25m long and 16 m respectively. Area of courtyard $=(25 \times 16) \mathrm{sq} \cdot \mathrm{m}^{2}=400 \mathrm{sq} \cdot \mathrm{m}^{2}$ Dimensions of bricks 20 cm by 10 cm Area of the surface of brick $=\left(\frac{20 \times 10}{10000}\right) \mathrm{m}^{2}$ $$\begin{aligned} \therefore \text { Number of bricks } & =\frac{400}{\frac{20 \times 10}{10000}} \\ & =\frac{400 \times 10000}{20 \times 10}=20000 \text { bricks } \end{aligned}$$
Explanation as extracted from the printed page; notation may be imperfect.