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Finding the Fourth Proportional to 648.31, 972.09 and 319.15

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Solution

The fourth proportional to 648.31, 972.09 and 319.15 is: 478.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.31 : 972.09 = 319.15 : x
  2. Step 2: Convert to fraction form
    648.31/972.09 = 319.15/x
  3. Step 3: Cross multiply
    648.31x = 972.09 × 319.15
  4. Step 4: Simplify right side
    648.31x = 310,242.52
  5. Step 5: Solve for x
    x = 310,242.52/648.31
  6. Step 6: Final answer
    x = 478.54

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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.