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Finding the Fourth Proportional to 528.78, 729.51 and 307.70

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Solution

The fourth proportional to 528.78, 729.51 and 307.70 is: 424.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.78 : 729.51 = 307.70 : x
  2. Step 2: Convert to fraction form
    528.78/729.51 = 307.70/x
  3. Step 3: Cross multiply
    528.78x = 729.51 × 307.70
  4. Step 4: Simplify right side
    528.78x = 224,470.23
  5. Step 5: Solve for x
    x = 224,470.23/528.78
  6. Step 6: Final answer
    x = 424.51

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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.