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Finding the Fourth Proportional to 80.25, 120.30 and 51.36

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Solution

The fourth proportional to 80.25, 120.30 and 51.36 is: 76.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.25 : 120.30 = 51.36 : x
  2. Step 2: Convert to fraction form
    80.25/120.30 = 51.36/x
  3. Step 3: Cross multiply
    80.25x = 120.30 × 51.36
  4. Step 4: Simplify right side
    80.25x = 6,178.61
  5. Step 5: Solve for x
    x = 6,178.61/80.25
  6. Step 6: Final answer
    x = 76.99

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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.