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Finding the Fourth Proportional to 654.60, 981.20 and 361.78

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Solution

The fourth proportional to 654.60, 981.20 and 361.78 is: 542.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.60 : 981.20 = 361.78 : x
  2. Step 2: Convert to fraction form
    654.60/981.20 = 361.78/x
  3. Step 3: Cross multiply
    654.60x = 981.20 × 361.78
  4. Step 4: Simplify right side
    654.60x = 354,978.54
  5. Step 5: Solve for x
    x = 354,978.54/654.60
  6. Step 6: Final answer
    x = 542.28

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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.