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Finding the Fourth Proportional to 74.79, 102.69 and 63.86

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Solution

The fourth proportional to 74.79, 102.69 and 63.86 is: 87.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    74.79 : 102.69 = 63.86 : x
  2. Step 2: Convert to fraction form
    74.79/102.69 = 63.86/x
  3. Step 3: Cross multiply
    74.79x = 102.69 × 63.86
  4. Step 4: Simplify right side
    74.79x = 6,557.27
  5. Step 5: Solve for x
    x = 6,557.27/74.79
  6. Step 6: Final answer
    x = 87.68

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.