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Finding the Fourth Proportional to 280.23, 386.91 and 206.70

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Solution

The fourth proportional to 280.23, 386.91 and 206.70 is: 285.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.23 : 386.91 = 206.70 : x
  2. Step 2: Convert to fraction form
    280.23/386.91 = 206.70/x
  3. Step 3: Cross multiply
    280.23x = 386.91 × 206.70
  4. Step 4: Simplify right side
    280.23x = 79,974.30
  5. Step 5: Solve for x
    x = 79,974.30/280.23
  6. Step 6: Final answer
    x = 285.39

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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.