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Finding the Fourth Proportional to 648.13, 972.21 and 257.97

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Solution

The fourth proportional to 648.13, 972.21 and 257.97 is: 386.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.13 : 972.21 = 257.97 : x
  2. Step 2: Convert to fraction form
    648.13/972.21 = 257.97/x
  3. Step 3: Cross multiply
    648.13x = 972.21 × 257.97
  4. Step 4: Simplify right side
    648.13x = 250,801.01
  5. Step 5: Solve for x
    x = 250,801.01/648.13
  6. Step 6: Final answer
    x = 386.96

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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.