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Finding the Fourth Proportional to 630.65, 869.85 and 394.71

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Solution

The fourth proportional to 630.65, 869.85 and 394.71 is: 544.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.65 : 869.85 = 394.71 : x
  2. Step 2: Convert to fraction form
    630.65/869.85 = 394.71/x
  3. Step 3: Cross multiply
    630.65x = 869.85 × 394.71
  4. Step 4: Simplify right side
    630.65x = 343,338.49
  5. Step 5: Solve for x
    x = 343,338.49/630.65
  6. Step 6: Final answer
    x = 544.42

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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.