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Finding the Fourth Proportional to 78.84, 108.86 and 75.64

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Solution

The fourth proportional to 78.84, 108.86 and 75.64 is: 104.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.84 : 108.86 = 75.64 : x
  2. Step 2: Convert to fraction form
    78.84/108.86 = 75.64/x
  3. Step 3: Cross multiply
    78.84x = 108.86 × 75.64
  4. Step 4: Simplify right side
    78.84x = 8,234.17
  5. Step 5: Solve for x
    x = 8,234.17/78.84
  6. Step 6: Final answer
    x = 104.44

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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.