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Finding the Fourth Proportional to 648.39, 972.50 and 209.69

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Solution

The fourth proportional to 648.39, 972.50 and 209.69 is: 314.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.39 : 972.50 = 209.69 : x
  2. Step 2: Convert to fraction form
    648.39/972.50 = 209.69/x
  3. Step 3: Cross multiply
    648.39x = 972.50 × 209.69
  4. Step 4: Simplify right side
    648.39x = 203,917.61
  5. Step 5: Solve for x
    x = 203,917.61/648.39
  6. Step 6: Final answer
    x = 314.50

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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.