Volume of a Cone - Frustum, GCSE Maths revision Exam paper practice

AQA Linked Paired Pilot Methods 2 Higher Practice Paper Question 17
Volume of a Cone - Frustum

[deelo]

Ik I'm seeing this 7 years after but I'm pretty sure the small triangle radius is 3
it is not a third times smaller than the bigger one as 1/3 times 1/3 is 1/9 not 2/3 but it does add a third so it would bt 1/3 add 1/3 in which is 2/3 and so you divide by 2 instead of three.

Essentially to get from 1/3 to 2/3 you add 1/3 not times by 1/3
Hence we divide 6 by 2 instead of 3 to get radius of3

am i right or am i waffling

[amybrown]

these videos are helping me get through GCSE - THANKYOU!

[enighaty]

If 2/3 is 6 1/3 is 6 because 2 times 3 is 6 which is 2/3 therefore 1/3 is 3

[RawMaths]

:) that always helps, but just in case you need a bit more, it is all about finding the radius and height of the two cones so you can find their volumes. Some times you need to use the information that is given in ratio of fractional form.

[h_wavey]

For the top height don't you use scale factor to figure it out? so 6/2=3 then 8/3=2.6

[drbs]

if the radius of the top triangle is 2cm then, by that rule, the height should be 8/3 which is 2.6cm?

[enighaty]

You've got me confused mate, the small triangle radius is three I swear

[lolasmith]

you need to cheer up coz i was sleeping