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Finding the Fourth Proportional to 256.40, 384.68 and 102.39

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Solution

The fourth proportional to 256.40, 384.68 and 102.39 is: 153.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    256.40 : 384.68 = 102.39 : x
  2. Step 2: Convert to fraction form
    256.40/384.68 = 102.39/x
  3. Step 3: Cross multiply
    256.40x = 384.68 × 102.39
  4. Step 4: Simplify right side
    256.40x = 39,386.87
  5. Step 5: Solve for x
    x = 39,386.87/256.40
  6. Step 6: Final answer
    x = 153.62

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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.