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Finding the Fourth Proportional to 344.20, 515.85 and 138.60

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Solution

The fourth proportional to 344.20, 515.85 and 138.60 is: 207.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    344.20 : 515.85 = 138.60 : x
  2. Step 2: Convert to fraction form
    344.20/515.85 = 138.60/x
  3. Step 3: Cross multiply
    344.20x = 515.85 × 138.60
  4. Step 4: Simplify right side
    344.20x = 71,496.81
  5. Step 5: Solve for x
    x = 71,496.81/344.20
  6. Step 6: Final answer
    x = 207.72

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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.