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Finding the Fourth Proportional to 638.61, 956.18 and 555.54

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Solution

The fourth proportional to 638.61, 956.18 and 555.54 is: 831.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.61 : 956.18 = 555.54 : x
  2. Step 2: Convert to fraction form
    638.61/956.18 = 555.54/x
  3. Step 3: Cross multiply
    638.61x = 956.18 × 555.54
  4. Step 4: Simplify right side
    638.61x = 531,193.46
  5. Step 5: Solve for x
    x = 531,193.46/638.61
  6. Step 6: Final answer
    x = 831.80

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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.