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Finding the Fourth Proportional to 138.99, 208.47 and 103.14

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Solution

The fourth proportional to 138.99, 208.47 and 103.14 is: 154.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.99 : 208.47 = 103.14 : x
  2. Step 2: Convert to fraction form
    138.99/208.47 = 103.14/x
  3. Step 3: Cross multiply
    138.99x = 208.47 × 103.14
  4. Step 4: Simplify right side
    138.99x = 21,501.60
  5. Step 5: Solve for x
    x = 21,501.60/138.99
  6. Step 6: Final answer
    x = 154.70

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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.