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Finding the Fourth Proportional to 421.61, 629.56 and 344.72

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Solution

The fourth proportional to 421.61, 629.56 and 344.72 is: 514.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.61 : 629.56 = 344.72 : x
  2. Step 2: Convert to fraction form
    421.61/629.56 = 344.72/x
  3. Step 3: Cross multiply
    421.61x = 629.56 × 344.72
  4. Step 4: Simplify right side
    421.61x = 217,021.92
  5. Step 5: Solve for x
    x = 217,021.92/421.61
  6. Step 6: Final answer
    x = 514.75

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.