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Finding the Fourth Proportional to 649.65, 972.57 and 429.87

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Solution

The fourth proportional to 649.65, 972.57 and 429.87 is: 643.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    649.65 : 972.57 = 429.87 : x
  2. Step 2: Convert to fraction form
    649.65/972.57 = 429.87/x
  3. Step 3: Cross multiply
    649.65x = 972.57 × 429.87
  4. Step 4: Simplify right side
    649.65x = 418,078.67
  5. Step 5: Solve for x
    x = 418,078.67/649.65
  6. Step 6: Final answer
    x = 643.54

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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.