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Finding the Fourth Proportional to 253.20, 379.80 and 138.38

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Solution

The fourth proportional to 253.20, 379.80 and 138.38 is: 207.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    253.20 : 379.80 = 138.38 : x
  2. Step 2: Convert to fraction form
    253.20/379.80 = 138.38/x
  3. Step 3: Cross multiply
    253.20x = 379.80 × 138.38
  4. Step 4: Simplify right side
    253.20x = 52,554.44
  5. Step 5: Solve for x
    x = 52,554.44/253.20
  6. Step 6: Final answer
    x = 207.56

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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.