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Finding the Fourth Proportional to 256.65, 385.03 and 102.55

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Solution

The fourth proportional to 256.65, 385.03 and 102.55 is: 153.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    256.65 : 385.03 = 102.55 : x
  2. Step 2: Convert to fraction form
    256.65/385.03 = 102.55/x
  3. Step 3: Cross multiply
    256.65x = 385.03 × 102.55
  4. Step 4: Simplify right side
    256.65x = 39,484.83
  5. Step 5: Solve for x
    x = 39,484.83/256.65
  6. Step 6: Final answer
    x = 153.85

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.