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Finding the Fourth Proportional to 80.61, 110.65 and 76

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Solution

The fourth proportional to 80.61, 110.65 and 76 is: 104.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.61 : 110.65 = 76 : x
  2. Step 2: Convert to fraction form
    80.61/110.65 = 76/x
  3. Step 3: Cross multiply
    80.61x = 110.65 × 76
  4. Step 4: Simplify right side
    80.61x = 8,409.02
  5. Step 5: Solve for x
    x = 8,409.02/80.61
  6. Step 6: Final answer
    x = 104.32

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.