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Finding the Fourth Proportional to 528.61, 729.27 and 318.80

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Solution

The fourth proportional to 528.61, 729.27 and 318.80 is: 439.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.61 : 729.27 = 318.80 : x
  2. Step 2: Convert to fraction form
    528.61/729.27 = 318.80/x
  3. Step 3: Cross multiply
    528.61x = 729.27 × 318.80
  4. Step 4: Simplify right side
    528.61x = 232,491.28
  5. Step 5: Solve for x
    x = 232,491.28/528.61
  6. Step 6: Final answer
    x = 439.82

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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.