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Finding the Fourth Proportional to 630.50, 870.21 and 381.96

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Solution

The fourth proportional to 630.50, 870.21 and 381.96 is: 527.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.50 : 870.21 = 381.96 : x
  2. Step 2: Convert to fraction form
    630.50/870.21 = 381.96/x
  3. Step 3: Cross multiply
    630.50x = 870.21 × 381.96
  4. Step 4: Simplify right side
    630.50x = 332,385.41
  5. Step 5: Solve for x
    x = 332,385.41/630.50
  6. Step 6: Final answer
    x = 527.18

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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.