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Finding the Fourth Proportional to 547.20, 820.80 and 424.80

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Solution

The fourth proportional to 547.20, 820.80 and 424.80 is: 637.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    547.20 : 820.80 = 424.80 : x
  2. Step 2: Convert to fraction form
    547.20/820.80 = 424.80/x
  3. Step 3: Cross multiply
    547.20x = 820.80 × 424.80
  4. Step 4: Simplify right side
    547.20x = 348,675.84
  5. Step 5: Solve for x
    x = 348,675.84/547.20
  6. Step 6: Final answer
    x = 637.20

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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.