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Finding the Fourth Proportional to 256.20, 353.73 and 209.69

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Solution

The fourth proportional to 256.20, 353.73 and 209.69 is: 289.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    256.20 : 353.73 = 209.69 : x
  2. Step 2: Convert to fraction form
    256.20/353.73 = 209.69/x
  3. Step 3: Cross multiply
    256.20x = 353.73 × 209.69
  4. Step 4: Simplify right side
    256.20x = 74,173.99
  5. Step 5: Solve for x
    x = 74,173.99/256.20
  6. Step 6: Final answer
    x = 289.52

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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.