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Finding the Fourth Proportional to 85.38, 117.03 and 84.30

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Solution

The fourth proportional to 85.38, 117.03 and 84.30 is: 115.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.38 : 117.03 = 84.30 : x
  2. Step 2: Convert to fraction form
    85.38/117.03 = 84.30/x
  3. Step 3: Cross multiply
    85.38x = 117.03 × 84.30
  4. Step 4: Simplify right side
    85.38x = 9,865.63
  5. Step 5: Solve for x
    x = 9,865.63/85.38
  6. Step 6: Final answer
    x = 115.55

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.