Mathematics for IGCSE & O level - Proportion (Section 2 - No. 21)
If *y* varies inversely as *x*, what happens to *y* when *x* is multiplied by 0.5?
y is multiplied by 0.5
y is divided by 0.5
y is multiplied by 2
y remains unchanged
คำอธิบาย
If x is multiplied by 0.5, y becomes k/(0.5x), or 2(k/x), therefore y is multiplied by 2.