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Finding the Fourth Proportional to 103.07, 154.20 and 77.15

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Solution

The fourth proportional to 103.07, 154.20 and 77.15 is: 115.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    103.07 : 154.20 = 77.15 : x
  2. Step 2: Convert to fraction form
    103.07/154.20 = 77.15/x
  3. Step 3: Cross multiply
    103.07x = 154.20 × 77.15
  4. Step 4: Simplify right side
    103.07x = 11,897.20
  5. Step 5: Solve for x
    x = 11,897.20/103.07
  6. Step 6: Final answer
    x = 115.43

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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.