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Finding the Fourth Proportional to 649.20, 972.84 and 505.68

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Solution

The fourth proportional to 649.20, 972.84 and 505.68 is: 757.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    649.20 : 972.84 = 505.68 : x
  2. Step 2: Convert to fraction form
    649.20/972.84 = 505.68/x
  3. Step 3: Cross multiply
    649.20x = 972.84 × 505.68
  4. Step 4: Simplify right side
    649.20x = 491,945.73
  5. Step 5: Solve for x
    x = 491,945.73/649.20
  6. Step 6: Final answer
    x = 757.77

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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.