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Finding the Fourth Proportional to 280.50, 387.30 and 207

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Solution

The fourth proportional to 280.50, 387.30 and 207 is: 285.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.50 : 387.30 = 207 : x
  2. Step 2: Convert to fraction form
    280.50/387.30 = 207/x
  3. Step 3: Cross multiply
    280.50x = 387.30 × 207
  4. Step 4: Simplify right side
    280.50x = 80,171.10
  5. Step 5: Solve for x
    x = 80,171.10/280.50
  6. Step 6: Final answer
    x = 285.81

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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.