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Finding the Fourth Proportional to 86.93, 130.49 and 66.61

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Solution

The fourth proportional to 86.93, 130.49 and 66.61 is: 99.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.93 : 130.49 = 66.61 : x
  2. Step 2: Convert to fraction form
    86.93/130.49 = 66.61/x
  3. Step 3: Cross multiply
    86.93x = 130.49 × 66.61
  4. Step 4: Simplify right side
    86.93x = 8,691.94
  5. Step 5: Solve for x
    x = 8,691.94/86.93
  6. Step 6: Final answer
    x = 99.99

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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.