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Finding the Fourth Proportional to 86.82, 130.28 and 59.78

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Solution

The fourth proportional to 86.82, 130.28 and 59.78 is: 89.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.82 : 130.28 = 59.78 : x
  2. Step 2: Convert to fraction form
    86.82/130.28 = 59.78/x
  3. Step 3: Cross multiply
    86.82x = 130.28 × 59.78
  4. Step 4: Simplify right side
    86.82x = 7,788.17
  5. Step 5: Solve for x
    x = 7,788.17/86.82
  6. Step 6: Final answer
    x = 89.71

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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.