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Finding the Fourth Proportional to 78.26, 108.13 and 63.68

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Solution

The fourth proportional to 78.26, 108.13 and 63.68 is: 87.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.26 : 108.13 = 63.68 : x
  2. Step 2: Convert to fraction form
    78.26/108.13 = 63.68/x
  3. Step 3: Cross multiply
    78.26x = 108.13 × 63.68
  4. Step 4: Simplify right side
    78.26x = 6,885.72
  5. Step 5: Solve for x
    x = 6,885.72/78.26
  6. Step 6: Final answer
    x = 87.99

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.