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Finding the Fourth Proportional to 60.78, 90.68 and 54.71

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Solution

The fourth proportional to 60.78, 90.68 and 54.71 is: 81.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    60.78 : 90.68 = 54.71 : x
  2. Step 2: Convert to fraction form
    60.78/90.68 = 54.71/x
  3. Step 3: Cross multiply
    60.78x = 90.68 × 54.71
  4. Step 4: Simplify right side
    60.78x = 4,961.10
  5. Step 5: Solve for x
    x = 4,961.10/60.78
  6. Step 6: Final answer
    x = 81.62

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.