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Finding the Fourth Proportional to 354.57, 489.20 and 256.45

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Solution

The fourth proportional to 354.57, 489.20 and 256.45 is: 353.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    354.57 : 489.20 = 256.45 : x
  2. Step 2: Convert to fraction form
    354.57/489.20 = 256.45/x
  3. Step 3: Cross multiply
    354.57x = 489.20 × 256.45
  4. Step 4: Simplify right side
    354.57x = 125,455.34
  5. Step 5: Solve for x
    x = 125,455.34/354.57
  6. Step 6: Final answer
    x = 353.82

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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.