Hey there! Sign in to join this conversationNew here? Join for free
    • Thread Starter

    The question reads as follows "Two spheres have radii in rati 5:3. Circle the ratio of their volumes: 5:3, 15:9, 25:9, 125:27". Answer is not what I'm interested in, but more so on how to solve other maths questions like these in the future (Or tomorrow, because I have a test)

    If two spheres have the same radii, then they will be the same volume. Or in this case you have a ratio. If a one spheres is in the ratio 5:3 compared to another sphere, the volume will be in that ratio as well.

    This is because there is only one variable you need when working out volume of a sphere (radius)

     V \propto r^3 , so you have to cube the ratio too, so it will be 53 :33 so 125 : 27 .
Do you agree with the PM's proposal to cut tuition fees for some courses?
Useful resources

Study tools


Essay expert

Learn to write like a pro with our ultimate essay guide.

Thinking about uni already?

Thinking about uni already?

See where you can apply with our uni match tool

Student chat

Ask a question

Chat to other GCSE students and get your study questions answered.


Make study resources

Create all the resources you need to get the grades.


Create your own Study Plan

Organise all your homework and exams so you never miss another deadline.

Resources by subject

From flashcards to mind maps; there's everything you need for all of your GCSE subjects.


Find past papers

100s of GCSE past papers for all your subjects at your fingertips.

Help out other students

Can you help? Study help unanswered threads

Groups associated with this forum:

View associated groups

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Write a reply...
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.