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Finding the Fourth Proportional to 281.20, 387.48 and 207.40

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Solution

The fourth proportional to 281.20, 387.48 and 207.40 is: 285.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    281.20 : 387.48 = 207.40 : x
  2. Step 2: Convert to fraction form
    281.20/387.48 = 207.40/x
  3. Step 3: Cross multiply
    281.20x = 387.48 × 207.40
  4. Step 4: Simplify right side
    281.20x = 80,363.35
  5. Step 5: Solve for x
    x = 80,363.35/281.20
  6. Step 6: Final answer
    x = 285.79

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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.