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Finding the Fourth Proportional to 630.65, 870.03 and 381.84

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Solution

The fourth proportional to 630.65, 870.03 and 381.84 is: 526.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.65 : 870.03 = 381.84 : x
  2. Step 2: Convert to fraction form
    630.65/870.03 = 381.84/x
  3. Step 3: Cross multiply
    630.65x = 870.03 × 381.84
  4. Step 4: Simplify right side
    630.65x = 332,212.26
  5. Step 5: Solve for x
    x = 332,212.26/630.65
  6. Step 6: Final answer
    x = 526.78

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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.