Question : The radius and slant height of a cone are in the ratio 5 : 7. If its curved surface area is 1347.5 cm2, find its radius. $\mathrm{(Use ~\pi =\frac{22}{7})}$
Option 1: 15 cm
Option 2: 25.5 cm
Option 3: 17.5 cm
Option 4: 21 cm
New: SSC CHSL Tier 2 answer key released | SSC CHSL 2024 Notification PDF
Recommended: How to crack SSC CHSL | SSC CHSL exam guide
Don't Miss: Month-wise Current Affairs | Upcoming government exams
New: Unlock 10% OFF on PTE Academic. Use Code: 'C360SPL10'
Correct Answer: 17.5 cm
Solution : Given, Radius : Slant height = 5 : 7 Let radius = 5$m$ and slant height = 7$m$ Curved surface area of the cone = 1347.5 cm 2 ⇒ $1347.5=\pi\times 5m\times 7m$ ⇒ $1347.5=\frac{22}{7}\times 35m^2$ ⇒ $m^2 = \frac{1347.5\times 7}{22\times 35}$ ⇒ $m^2 = \frac{9432.5}{770}=12.25$ ⇒ $m = \sqrt{12.25}=3.5$ So, the radius $= 5\times3.5 = 17.5$ cm Hence, the correct answer is 17.5 cm.
Candidates can download this e-book to give a boost to thier preparation.
Result | Eligibility | Application | Admit Card | Answer Key | Preparation Tips | Cutoff
Question : If the height and slant height of a cone are 21 cm and 29 cm, respectively. Find its volume. (Use $\pi=\frac{22}{7}$)
Question : If the slant height and radius of a right circular cone are 28 cm and 21 cm, respectively, then the total surface area of the right circular cone (in cm2) is: (Take $\pi=\frac{22}{7}$)
Question : The curved surface area of a right circular cone of diameter $42 \ \text{cm}$ is $990 \ \text{cm}^2$. What is the slant height (in${\ \text{cm}})$ of the cone? [Use $\pi=\frac{22}{7}$]
Question : The total surface area of a cylinder whose radius is 6 cm and height is 8 cm is: (Use $\pi=\frac{22}{7}$)
Question : If the curved surface area of a cylinder is 1386 sq cm and the height is 21 cm, what will be its radius? (Take $\pi=\frac{22}{7}$)
Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile