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Finding the Fourth Proportional to 78.88, 109.05 and 75.48

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Solution

The fourth proportional to 78.88, 109.05 and 75.48 is: 104.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.88 : 109.05 = 75.48 : x
  2. Step 2: Convert to fraction form
    78.88/109.05 = 75.48/x
  3. Step 3: Cross multiply
    78.88x = 109.05 × 75.48
  4. Step 4: Simplify right side
    78.88x = 8,231.09
  5. Step 5: Solve for x
    x = 8,231.09/78.88
  6. Step 6: Final answer
    x = 104.35

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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.