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Finding the Fourth Proportional to 392.12, 541.02 and 280.40

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Solution

The fourth proportional to 392.12, 541.02 and 280.40 is: 386.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    392.12 : 541.02 = 280.40 : x
  2. Step 2: Convert to fraction form
    392.12/541.02 = 280.40/x
  3. Step 3: Cross multiply
    392.12x = 541.02 × 280.40
  4. Step 4: Simplify right side
    392.12x = 151,702.01
  5. Step 5: Solve for x
    x = 151,702.01/392.12
  6. Step 6: Final answer
    x = 386.88

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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.