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Finding the Fourth Proportional to 630.43, 869.78 and 381.65

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Solution

The fourth proportional to 630.43, 869.78 and 381.65 is: 526.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.43 : 869.78 = 381.65 : x
  2. Step 2: Convert to fraction form
    630.43/869.78 = 381.65/x
  3. Step 3: Cross multiply
    630.43x = 869.78 × 381.65
  4. Step 4: Simplify right side
    630.43x = 331,954.67
  5. Step 5: Solve for x
    x = 331,954.67/630.43
  6. Step 6: Final answer
    x = 526.55

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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.