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Finding the Fourth Proportional to 86.77, 129.85 and 61.03

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Solution

The fourth proportional to 86.77, 129.85 and 61.03 is: 91.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.77 : 129.85 = 61.03 : x
  2. Step 2: Convert to fraction form
    86.77/129.85 = 61.03/x
  3. Step 3: Cross multiply
    86.77x = 129.85 × 61.03
  4. Step 4: Simplify right side
    86.77x = 7,924.75
  5. Step 5: Solve for x
    x = 7,924.75/86.77
  6. Step 6: Final answer
    x = 91.33

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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.