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Finding the Fourth Proportional to 920.20, 1,380.20 and 343

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Solution

The fourth proportional to 920.20, 1,380.20 and 343 is: 514.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    920.20 : 1,380.20 = 343 : x
  2. Step 2: Convert to fraction form
    920.20/1,380.20 = 343/x
  3. Step 3: Cross multiply
    920.20x = 1,380.20 × 343
  4. Step 4: Simplify right side
    920.20x = 473,408.60
  5. Step 5: Solve for x
    x = 473,408.60/920.20
  6. Step 6: Final answer
    x = 514.46

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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.