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Finding the Fourth Proportional to 402.80, 605.55 and 343.40

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Solution

The fourth proportional to 402.80, 605.55 and 343.40 is: 516.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    402.80 : 605.55 = 343.40 : x
  2. Step 2: Convert to fraction form
    402.80/605.55 = 343.40/x
  3. Step 3: Cross multiply
    402.80x = 605.55 × 343.40
  4. Step 4: Simplify right side
    402.80x = 207,945.87
  5. Step 5: Solve for x
    x = 207,945.87/402.80
  6. Step 6: Final answer
    x = 516.25

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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.