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Finding the Fourth Proportional to 86.53, 129.79 and 76.50

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Solution

The fourth proportional to 86.53, 129.79 and 76.50 is: 114.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.53 : 129.79 = 76.50 : x
  2. Step 2: Convert to fraction form
    86.53/129.79 = 76.50/x
  3. Step 3: Cross multiply
    86.53x = 129.79 × 76.50
  4. Step 4: Simplify right side
    86.53x = 9,929.29
  5. Step 5: Solve for x
    x = 9,929.29/86.53
  6. Step 6: Final answer
    x = 114.75

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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.