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Finding the Fourth Proportional to 630.55, 870.02 and 381.88

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Solution

The fourth proportional to 630.55, 870.02 and 381.88 is: 526.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.55 : 870.02 = 381.88 : x
  2. Step 2: Convert to fraction form
    630.55/870.02 = 381.88/x
  3. Step 3: Cross multiply
    630.55x = 870.02 × 381.88
  4. Step 4: Simplify right side
    630.55x = 332,246.00
  5. Step 5: Solve for x
    x = 332,246.00/630.55
  6. Step 6: Final answer
    x = 526.91

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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.