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Finding the Fourth Proportional to 102.85, 154.05 and 83.55

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Solution

The fourth proportional to 102.85, 154.05 and 83.55 is: 125.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    102.85 : 154.05 = 83.55 : x
  2. Step 2: Convert to fraction form
    102.85/154.05 = 83.55/x
  3. Step 3: Cross multiply
    102.85x = 154.05 × 83.55
  4. Step 4: Simplify right side
    102.85x = 12,870.88
  5. Step 5: Solve for x
    x = 12,870.88/102.85
  6. Step 6: Final answer
    x = 125.14

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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.