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Finding the Fourth Proportional to 256.05, 384.09 and 80.32

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Solution

The fourth proportional to 256.05, 384.09 and 80.32 is: 120.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    256.05 : 384.09 = 80.32 : x
  2. Step 2: Convert to fraction form
    256.05/384.09 = 80.32/x
  3. Step 3: Cross multiply
    256.05x = 384.09 × 80.32
  4. Step 4: Simplify right side
    256.05x = 30,850.11
  5. Step 5: Solve for x
    x = 30,850.11/256.05
  6. Step 6: Final answer
    x = 120.48

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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.