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Finding the Fourth Proportional to 528.64, 729.28 and 321.76

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Solution

The fourth proportional to 528.64, 729.28 and 321.76 is: 443.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.64 : 729.28 = 321.76 : x
  2. Step 2: Convert to fraction form
    528.64/729.28 = 321.76/x
  3. Step 3: Cross multiply
    528.64x = 729.28 × 321.76
  4. Step 4: Simplify right side
    528.64x = 234,653.13
  5. Step 5: Solve for x
    x = 234,653.13/528.64
  6. Step 6: Final answer
    x = 443.88

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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.