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Finding the Fourth Proportional to 629.85, 868.51 and 393.71

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Solution

The fourth proportional to 629.85, 868.51 and 393.71 is: 542.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    629.85 : 868.51 = 393.71 : x
  2. Step 2: Convert to fraction form
    629.85/868.51 = 393.71/x
  3. Step 3: Cross multiply
    629.85x = 868.51 × 393.71
  4. Step 4: Simplify right side
    629.85x = 341,941.07
  5. Step 5: Solve for x
    x = 341,941.07/629.85
  6. Step 6: Final answer
    x = 542.89

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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.