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Finding the Fourth Proportional to 86.78, 130.10 and 41.12

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Solution

The fourth proportional to 86.78, 130.10 and 41.12 is: 61.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.78 : 130.10 = 41.12 : x
  2. Step 2: Convert to fraction form
    86.78/130.10 = 41.12/x
  3. Step 3: Cross multiply
    86.78x = 130.10 × 41.12
  4. Step 4: Simplify right side
    86.78x = 5,349.71
  5. Step 5: Solve for x
    x = 5,349.71/86.78
  6. Step 6: Final answer
    x = 61.65

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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.