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Finding the Fourth Proportional to 528.72, 728.64 and 381.12

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Solution

The fourth proportional to 528.72, 728.64 and 381.12 is: 525.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.72 : 728.64 = 381.12 : x
  2. Step 2: Convert to fraction form
    528.72/728.64 = 381.12/x
  3. Step 3: Cross multiply
    528.72x = 728.64 × 381.12
  4. Step 4: Simplify right side
    528.72x = 277,699.28
  5. Step 5: Solve for x
    x = 277,699.28/528.72
  6. Step 6: Final answer
    x = 525.23

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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.