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Finding the Fourth Proportional to 477.20, 715.80 and 285.20

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Solution

The fourth proportional to 477.20, 715.80 and 285.20 is: 427.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    477.20 : 715.80 = 285.20 : x
  2. Step 2: Convert to fraction form
    477.20/715.80 = 285.20/x
  3. Step 3: Cross multiply
    477.20x = 715.80 × 285.20
  4. Step 4: Simplify right side
    477.20x = 204,146.16
  5. Step 5: Solve for x
    x = 204,146.16/477.20
  6. Step 6: Final answer
    x = 427.80

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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.