2026 PCSS P1 Q18

\(y\) is directly proportional to the cube root of \(x\).

It is given that \(y=50\) for a certain value of \(x\).

Find the value of \(y\) when this value of \(x\) decreased by 87.5%.[3]

A rectangular notice board is being redesigned. Its length is reduced by 20% while its breadth is increased by 20%.

A student claims that the area of the notice board will remain unchanged because the percentage decrease and percentage increase are equal.

Determine whether the student's claim is correct. Support your answer with mathematical calculations.[3]