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Finding the Fourth Proportional to 343.71, 515.61 and 138.47

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Solution

The fourth proportional to 343.71, 515.61 and 138.47 is: 207.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    343.71 : 515.61 = 138.47 : x
  2. Step 2: Convert to fraction form
    343.71/515.61 = 138.47/x
  3. Step 3: Cross multiply
    343.71x = 515.61 × 138.47
  4. Step 4: Simplify right side
    343.71x = 71,393.94
  5. Step 5: Solve for x
    x = 71,393.94/343.71
  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.