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Finding the Fourth Proportional to 80.23, 110.85 and 72.79

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Solution

The fourth proportional to 80.23, 110.85 and 72.79 is: 100.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.23 : 110.85 = 72.79 : x
  2. Step 2: Convert to fraction form
    80.23/110.85 = 72.79/x
  3. Step 3: Cross multiply
    80.23x = 110.85 × 72.79
  4. Step 4: Simplify right side
    80.23x = 8,068.77
  5. Step 5: Solve for x
    x = 8,068.77/80.23
  6. Step 6: Final answer
    x = 100.57

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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.