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Finding the Fourth Proportional to 280.70, 387.33 and 207.05

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Solution

The fourth proportional to 280.70, 387.33 and 207.05 is: 285.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.70 : 387.33 = 207.05 : x
  2. Step 2: Convert to fraction form
    280.70/387.33 = 207.05/x
  3. Step 3: Cross multiply
    280.70x = 387.33 × 207.05
  4. Step 4: Simplify right side
    280.70x = 80,196.68
  5. Step 5: Solve for x
    x = 80,196.68/280.70
  6. Step 6: Final answer
    x = 285.71

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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.