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Finding the Fourth Proportional to 103.18, 154.56 and 85.15

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Solution

The fourth proportional to 103.18, 154.56 and 85.15 is: 127.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    103.18 : 154.56 = 85.15 : x
  2. Step 2: Convert to fraction form
    103.18/154.56 = 85.15/x
  3. Step 3: Cross multiply
    103.18x = 154.56 × 85.15
  4. Step 4: Simplify right side
    103.18x = 13,160.36
  5. Step 5: Solve for x
    x = 13,160.36/103.18
  6. Step 6: Final answer
    x = 127.55

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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.