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Finding the Fourth Proportional to 405.98, 609.28 and 308.78

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Solution

The fourth proportional to 405.98, 609.28 and 308.78 is: 463.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.98 : 609.28 = 308.78 : x
  2. Step 2: Convert to fraction form
    405.98/609.28 = 308.78/x
  3. Step 3: Cross multiply
    405.98x = 609.28 × 308.78
  4. Step 4: Simplify right side
    405.98x = 188,133.48
  5. Step 5: Solve for x
    x = 188,133.48/405.98
  6. Step 6: Final answer
    x = 463.41

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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.