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Finding the Fourth Proportional to 138.90, 207.26 and 135.80

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Solution

The fourth proportional to 138.90, 207.26 and 135.80 is: 202.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.90 : 207.26 = 135.80 : x
  2. Step 2: Convert to fraction form
    138.90/207.26 = 135.80/x
  3. Step 3: Cross multiply
    138.90x = 207.26 × 135.80
  4. Step 4: Simplify right side
    138.90x = 28,145.91
  5. Step 5: Solve for x
    x = 28,145.91/138.90
  6. Step 6: Final answer
    x = 202.63

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.