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Finding the Fourth Proportional to 85.59, 129.08 and 75.57

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Solution

The fourth proportional to 85.59, 129.08 and 75.57 is: 113.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.59 : 129.08 = 75.57 : x
  2. Step 2: Convert to fraction form
    85.59/129.08 = 75.57/x
  3. Step 3: Cross multiply
    85.59x = 129.08 × 75.57
  4. Step 4: Simplify right side
    85.59x = 9,754.58
  5. Step 5: Solve for x
    x = 9,754.58/85.59
  6. Step 6: Final answer
    x = 113.97

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.