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Finding the Fourth Proportional to 648.52, 972.80 and 209.76

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Solution

The fourth proportional to 648.52, 972.80 and 209.76 is: 314.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.52 : 972.80 = 209.76 : x
  2. Step 2: Convert to fraction form
    648.52/972.80 = 209.76/x
  3. Step 3: Cross multiply
    648.52x = 972.80 × 209.76
  4. Step 4: Simplify right side
    648.52x = 204,059.42
  5. Step 5: Solve for x
    x = 204,059.42/648.52
  6. Step 6: Final answer
    x = 314.65

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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.