Investment Ratio
Investment ratio problems require you to work backward. Instead of calculating profit, you will use given profit balances and time intervals to find unknown capital contributions.
Fundamental Principles
Capital Factor Isolation
An algebraic rearrangement of the core partnership balance used to find missing dimensions, written as: $\text{Investment Ratio} = \frac{\text{Profit Share}}{\text{Time Duration}}$.
Essential Formulation Tips
- Use a clear algebraic variable (like $x$) to represent the unknown investment value in your initial layout.
- Double-check that all fractional steps are completely cleared before running large multiplications.
Shortcut Execution Techniques
- The Ratio Equivalence Shortcut: Instead of using large cash values, scale investment sums down into simplified ratio units during intermediate algebra steps to keep your scratchpad math clean.
Contextual Inquiries (FAQs)
Q: What should I do if a problem contains two unknown investment values?
A: Look for a secondary clue, such as a statement linking their investments (e.g., 'A invested $500 more than B'), to build a single-variable equation.
Example Breakdown: Isolating Capital from Time-Profit Constraints
Standard algebraic capital isolation challenge.Let B's unknown capital investment be represented by $x$.
Set up the product ratio for both partners: $(\text{Investment}_A \times \text{Time}_A) : (\text{Investment}_B \times \text{Time}_B)$.
Substitute known values: $(2000 \times 8) : (x \times 6) = 16000 : 6x$.
Match the product ratio to the given profit split: $\frac{16000}{6x} = \frac{4}{3}$.
Cross-multiply to solve for your variable: $16000 \times 3 = 4 \times 6x \implies 48000 = 24x$.
Isolate the investment variable: $x = \frac{48000}{24} = 2000$.
Conclusion: B's capital input was exactly $2,000.
Capital Extraction Challenges
Practice working backward to isolate unknown capital inputs from time and profit constraints.
Q1. John and Mark share business profits in the ratio 2:3. John invested $4,000 for 9 months. If Mark invested his capital for 6 months, how much money did Mark invest?