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Finding the Fourth Proportional to 648.00, 972.28 and 339.78

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Solution

The fourth proportional to 648.00, 972.28 and 339.78 is: 509.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.00 : 972.28 = 339.78 : x
  2. Step 2: Convert to fraction form
    648.00/972.28 = 339.78/x
  3. Step 3: Cross multiply
    648.00x = 972.28 × 339.78
  4. Step 4: Simplify right side
    648.00x = 330,356.44
  5. Step 5: Solve for x
    x = 330,356.44/648.00
  6. Step 6: Final answer
    x = 509.81

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.