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Finding the Fourth Proportional to 256.05, 384.06 and 215.40

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Solution

The fourth proportional to 256.05, 384.06 and 215.40 is: 323.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    256.05 : 384.06 = 215.40 : x
  2. Step 2: Convert to fraction form
    256.05/384.06 = 215.40/x
  3. Step 3: Cross multiply
    256.05x = 384.06 × 215.40
  4. Step 4: Simplify right side
    256.05x = 82,726.52
  5. Step 5: Solve for x
    x = 82,726.52/256.05
  6. Step 6: Final answer
    x = 323.09

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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.