Subject: General Aptitude · Chapter: Area · Exam: · Marks: · Difficulty:
The perimeters of five squares are 24 cm, 32 cm, 40 cm, 76 cm and 80 cm respectively. The perimeter of another square equal in area to the sum of the areas of these squares is
(a)31 cm
(b)62 cm
(c)124 cm
(d)961 cm
Answer
Answer (as printed): C
Explanation
The sides of the five squares are $\left(\frac{24}{4}\right),\left(\frac{32}{4}\right),\left(\frac{40}{4}\right),\left(\frac{76}{4}\right),\left(\frac{80}{4}\right)$ i.e., 6 cm, 8 cm, 10 cm, 19 cm, 20 cm. ∴ Area of the new square $=\left[6^{2}+8^{2}+(10)^{2}+(19)^{2}+(20)^{2}\right]$ $$=(36+64+100+361+400) \mathrm{cm}^{2}=961 \mathrm{cm}^{2} .$$ Side of the new square $=\sqrt{961} \mathrm{cm}=31 \mathrm{cm}$. Perimeter of the new square $=(4 \times 31) \mathrm{cm}=124 \mathrm{cm}$.