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Finding the Fourth Proportional to 630.68, 870.13 and 381.90

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Solution

The fourth proportional to 630.68, 870.13 and 381.90 is: 526.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.68 : 870.13 = 381.90 : x
  2. Step 2: Convert to fraction form
    630.68/870.13 = 381.90/x
  3. Step 3: Cross multiply
    630.68x = 870.13 × 381.90
  4. Step 4: Simplify right side
    630.68x = 332,302.65
  5. Step 5: Solve for x
    x = 332,302.65/630.68
  6. Step 6: Final answer
    x = 526.90

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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.