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Finding the Fourth Proportional to 405.99, 609.10 and 220.86

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Solution

The fourth proportional to 405.99, 609.10 and 220.86 is: 331.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.99 : 609.10 = 220.86 : x
  2. Step 2: Convert to fraction form
    405.99/609.10 = 220.86/x
  3. Step 3: Cross multiply
    405.99x = 609.10 × 220.86
  4. Step 4: Simplify right side
    405.99x = 134,522.78
  5. Step 5: Solve for x
    x = 134,522.78/405.99
  6. Step 6: Final answer
    x = 331.35

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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.