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Finding the Fourth Proportional to 86.85, 130.17 and 66.51

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Solution

The fourth proportional to 86.85, 130.17 and 66.51 is: 99.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.85 : 130.17 = 66.51 : x
  2. Step 2: Convert to fraction form
    86.85/130.17 = 66.51/x
  3. Step 3: Cross multiply
    86.85x = 130.17 × 66.51
  4. Step 4: Simplify right side
    86.85x = 8,657.61
  5. Step 5: Solve for x
    x = 8,657.61/86.85
  6. Step 6: Final answer
    x = 99.68

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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.