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Finding the Fourth Proportional to 80.04, 110.92 and 78.72

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Solution

The fourth proportional to 80.04, 110.92 and 78.72 is: 109.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.04 : 110.92 = 78.72 : x
  2. Step 2: Convert to fraction form
    80.04/110.92 = 78.72/x
  3. Step 3: Cross multiply
    80.04x = 110.92 × 78.72
  4. Step 4: Simplify right side
    80.04x = 8,731.78
  5. Step 5: Solve for x
    x = 8,731.78/80.04
  6. Step 6: Final answer
    x = 109.10

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.