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Finding the Fourth Proportional to 80.48, 120.63 and 55.79

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Solution

The fourth proportional to 80.48, 120.63 and 55.79 is: 83.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.48 : 120.63 = 55.79 : x
  2. Step 2: Convert to fraction form
    80.48/120.63 = 55.79/x
  3. Step 3: Cross multiply
    80.48x = 120.63 × 55.79
  4. Step 4: Simplify right side
    80.48x = 6,729.95
  5. Step 5: Solve for x
    x = 6,729.95/80.48
  6. Step 6: Final answer
    x = 83.62

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.