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Finding the Fourth Proportional to 402.87, 555.71 and 355.49

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Solution

The fourth proportional to 402.87, 555.71 and 355.49 is: 490.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    402.87 : 555.71 = 355.49 : x
  2. Step 2: Convert to fraction form
    402.87/555.71 = 355.49/x
  3. Step 3: Cross multiply
    402.87x = 555.71 × 355.49
  4. Step 4: Simplify right side
    402.87x = 197,548.88
  5. Step 5: Solve for x
    x = 197,548.88/402.87
  6. Step 6: Final answer
    x = 490.35

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.