A circle, of radius r = radius of the sphere
you can think of it in terms of projection the plan projection of the sphere is a circle.
The answer will be y^2/4 (I’ve written up properly on the photo as I can’t type it)
Answer:
we express the ratio of pencil to eraser and multiply it by the number of the number of pencils and erasers. 4/5 * x=20 , so x=25, then it implies that there are 5 erasers.
