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Finding the Fourth Proportional to 630.65, 870.39 and 381.98

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Solution

The fourth proportional to 630.65, 870.39 and 381.98 is: 527.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.65 : 870.39 = 381.98 : x
  2. Step 2: Convert to fraction form
    630.65/870.39 = 381.98/x
  3. Step 3: Cross multiply
    630.65x = 870.39 × 381.98
  4. Step 4: Simplify right side
    630.65x = 332,467.22
  5. Step 5: Solve for x
    x = 332,467.22/630.65
  6. Step 6: Final answer
    x = 527.19

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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.