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Finding the Fourth Proportional to 402.70, 605.06 and 256.51

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Solution

The fourth proportional to 402.70, 605.06 and 256.51 is: 385.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    402.70 : 605.06 = 256.51 : x
  2. Step 2: Convert to fraction form
    402.70/605.06 = 256.51/x
  3. Step 3: Cross multiply
    402.70x = 605.06 × 256.51
  4. Step 4: Simplify right side
    402.70x = 155,204.87
  5. Step 5: Solve for x
    x = 155,204.87/402.70
  6. Step 6: Final answer
    x = 385.41

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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.