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Finding the Fourth Proportional to 280.57, 387.29 and 207.47

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Solution

The fourth proportional to 280.57, 387.29 and 207.47 is: 286.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.57 : 387.29 = 207.47 : x
  2. Step 2: Convert to fraction form
    280.57/387.29 = 207.47/x
  3. Step 3: Cross multiply
    280.57x = 387.29 × 207.47
  4. Step 4: Simplify right side
    280.57x = 80,350.02
  5. Step 5: Solve for x
    x = 80,350.02/280.57
  6. Step 6: Final answer
    x = 286.39

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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.