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Finding the Fourth Proportional to 629.55, 869.16 and 420.03

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Solution

The fourth proportional to 629.55, 869.16 and 420.03 is: 579.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    629.55 : 869.16 = 420.03 : x
  2. Step 2: Convert to fraction form
    629.55/869.16 = 420.03/x
  3. Step 3: Cross multiply
    629.55x = 869.16 × 420.03
  4. Step 4: Simplify right side
    629.55x = 365,073.27
  5. Step 5: Solve for x
    x = 365,073.27/629.55
  6. Step 6: Final answer
    x = 579.90

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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.