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Finding the Fourth Proportional to 419.78, 628.18 and 309.83

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Solution

The fourth proportional to 419.78, 628.18 and 309.83 is: 463.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.78 : 628.18 = 309.83 : x
  2. Step 2: Convert to fraction form
    419.78/628.18 = 309.83/x
  3. Step 3: Cross multiply
    419.78x = 628.18 × 309.83
  4. Step 4: Simplify right side
    419.78x = 194,629.01
  5. Step 5: Solve for x
    x = 194,629.01/419.78
  6. Step 6: Final answer
    x = 463.65

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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.