A cylinder of base radius 2x and height 3x has the same volume as a cone of base radius 3x and height h. Find h in terms of x.

The equation for the volume of a cylinder is (1/2)pi(r2)*H, where r is the radius and H is the height of the cylinder. For the cylinder given, the volume is therefore (1/2)pi((2x)2)*3x, or more simply: 6x3*pi. The equation for the volume of a cone is (1/3)pi((r2)*H, where r is again the radius and H is again the height of the cone. For the cone given, the volume is therefore (1/3)pi((3x)2)*h, or more simply: 3x2pih. Since the volume of the cylinder is equal to the volume of the cone, we can say that:6x3*pi = 3x2pih. By dividing both sides of the equation by pi, and then both sides of the equation by 3x2, we can determine that h=2x.

Answered by Georgie F. Maths tutor

5763 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Solve the simultaneous equations: 6a + b = 16 and 5a - 2b = 19


John invests £8000 at compound interest rate of 1.5% per year. He wants to earn more than £2000 in interest. What is the LEAST time in WHOLE years that this will take?


How do you expand brackets? eg. (2x+3)(3x+4)


A ladder 6·8m long is leaning against a wall. The foot of the ladder is 1·5m from the wall. Calculate the distance the ladder reaches up the wall.


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo
Cookie Preferences