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Finding the Fourth Proportional to 391.54, 540.38 and 281.38

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Solution

The fourth proportional to 391.54, 540.38 and 281.38 is: 388.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.54 : 540.38 = 281.38 : x
  2. Step 2: Convert to fraction form
    391.54/540.38 = 281.38/x
  3. Step 3: Cross multiply
    391.54x = 540.38 × 281.38
  4. Step 4: Simplify right side
    391.54x = 152,051.48
  5. Step 5: Solve for x
    x = 152,051.48/391.54
  6. Step 6: Final answer
    x = 388.34

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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.