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Finding the Fourth Proportional to 648.29, 971.34 and 391.25

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Solution

The fourth proportional to 648.29, 971.34 and 391.25 is: 586.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.29 : 971.34 = 391.25 : x
  2. Step 2: Convert to fraction form
    648.29/971.34 = 391.25/x
  3. Step 3: Cross multiply
    648.29x = 971.34 × 391.25
  4. Step 4: Simplify right side
    648.29x = 380,034.82
  5. Step 5: Solve for x
    x = 380,034.82/648.29
  6. Step 6: Final answer
    x = 586.21

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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.