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Finding the Fourth Proportional to 555.30, 831.42 and 381.78

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Solution

The fourth proportional to 555.30, 831.42 and 381.78 is: 571.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    555.30 : 831.42 = 381.78 : x
  2. Step 2: Convert to fraction form
    555.30/831.42 = 381.78/x
  3. Step 3: Cross multiply
    555.30x = 831.42 × 381.78
  4. Step 4: Simplify right side
    555.30x = 317,419.53
  5. Step 5: Solve for x
    x = 317,419.53/555.30
  6. Step 6: Final answer
    x = 571.62

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.