A typist uses a paper 30 cm by 15 cm. He leaves a margin of 2.5 cm at the top and bottom and 1.25 cm on… · ABC26GN4360
Subject: General Aptitude · Chapter: Area · Exam: R.R.B. 2006
A typist uses a paper 30 cm by 15 cm. He leaves a margin of 2.5 cm at the top and bottom and 1.25 cm on either side. What percentage of paper area is approximately available for typing?
(a)60\%
(b)65\%
(c)70\%
(d)80\%
Answer
Answer (as printed): C
Explanation
Area of the sheet $=(30 \times 15) \mathrm{cm}^{2}=45 \mathrm{cm}^{2}$. Area used for typing $=[(30-5) \times(15-2.5)] \mathrm{cm}^{2}=312.5$ $\mathrm{cm}^{2}$. $$\text { ∴ } \text { Required percentage }=\left(\frac{312.5}{450} \times 100\right) \%=69.4 \% \approx 70 \% .$$