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Finding the Fourth Proportional to 289.40, 434.10 and 220.55

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Solution

The fourth proportional to 289.40, 434.10 and 220.55 is: 330.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    289.40 : 434.10 = 220.55 : x
  2. Step 2: Convert to fraction form
    289.40/434.10 = 220.55/x
  3. Step 3: Cross multiply
    289.40x = 434.10 × 220.55
  4. Step 4: Simplify right side
    289.40x = 95,740.76
  5. Step 5: Solve for x
    x = 95,740.76/289.40
  6. Step 6: Final answer
    x = 330.83

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.