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Finding the Fourth Proportional to 85.20, 115.02 and 85.20

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Solution

The fourth proportional to 85.20, 115.02 and 85.20 is: 115.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.20 : 115.02 = 85.20 : x
  2. Step 2: Convert to fraction form
    85.20/115.02 = 85.20/x
  3. Step 3: Cross multiply
    85.20x = 115.02 × 85.20
  4. Step 4: Simplify right side
    85.20x = 9,799.70
  5. Step 5: Solve for x
    x = 9,799.70/85.20
  6. Step 6: Final answer
    x = 115.02

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Why These Related Problems?

These problems maintain the same ratio (1.35) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.