Common Ratio

The common ratio $r$ is the fixed factor by which each term of a geometric progression is multiplied to get the next, found by $r=\frac{T_n}{T_{n-1}}$. If $|r|>1$ the terms grow, and if $|r|<1$ they shrink towards zero, which allows a sum to infinity.

You meet Common Ratio in the Progressions chapter of SPM Additional Mathematics. Knowing the term precisely matters in the exam: questions often hinge on reading a keyword correctly, and because SPM marking is analytic, using the right definition in your working helps secure method marks.

Our teachers make sure a student can not only recite what Common Ratio means but use it fluently in a full solution.

Because the SPM Add Math paper is bilingual (BM/EN), it helps to know this term in each language: Common Ratio (EN) · Nisbah Sepunya (BM) · 公比 (中文)

Other key terms from the Progressions chapter you may want to check:

• Sequence
• Arithmetic Progression
• Common Difference
• Geometric Progression
• nth Term
• Sum of the First n Terms