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Finding the Fourth Proportional to 528.13, 728.89 and 318.31

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Solution

The fourth proportional to 528.13, 728.89 and 318.31 is: 439.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.13 : 728.89 = 318.31 : x
  2. Step 2: Convert to fraction form
    528.13/728.89 = 318.31/x
  3. Step 3: Cross multiply
    528.13x = 728.89 × 318.31
  4. Step 4: Simplify right side
    528.13x = 232,012.47
  5. Step 5: Solve for x
    x = 232,012.47/528.13
  6. Step 6: Final answer
    x = 439.31

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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.