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Finding the Fourth Proportional to 629.92, 868.80 and 419.72

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Solution

The fourth proportional to 629.92, 868.80 and 419.72 is: 578.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    629.92 : 868.80 = 419.72 : x
  2. Step 2: Convert to fraction form
    629.92/868.80 = 419.72/x
  3. Step 3: Cross multiply
    629.92x = 868.80 × 419.72
  4. Step 4: Simplify right side
    629.92x = 364,652.74
  5. Step 5: Solve for x
    x = 364,652.74/629.92
  6. Step 6: Final answer
    x = 578.89

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.