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Finding the Fourth Proportional to 80.59, 110.87 and 71.21

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Solution

The fourth proportional to 80.59, 110.87 and 71.21 is: 97.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.59 : 110.87 = 71.21 : x
  2. Step 2: Convert to fraction form
    80.59/110.87 = 71.21/x
  3. Step 3: Cross multiply
    80.59x = 110.87 × 71.21
  4. Step 4: Simplify right side
    80.59x = 7,894.14
  5. Step 5: Solve for x
    x = 7,894.14/80.59
  6. Step 6: Final answer
    x = 97.96

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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.