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Finding the Fourth Proportional to 585.20, 807.72 and 419.78

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Solution

The fourth proportional to 585.20, 807.72 and 419.78 is: 579.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    585.20 : 807.72 = 419.78 : x
  2. Step 2: Convert to fraction form
    585.20/807.72 = 419.78/x
  3. Step 3: Cross multiply
    585.20x = 807.72 × 419.78
  4. Step 4: Simplify right side
    585.20x = 339,064.70
  5. Step 5: Solve for x
    x = 339,064.70/585.20
  6. Step 6: Final answer
    x = 579.40

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.