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Finding the Fourth Proportional to 120.30, 180.49 and 51.80

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Solution

The fourth proportional to 120.30, 180.49 and 51.80 is: 77.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    120.30 : 180.49 = 51.80 : x
  2. Step 2: Convert to fraction form
    120.30/180.49 = 51.80/x
  3. Step 3: Cross multiply
    120.30x = 180.49 × 51.80
  4. Step 4: Simplify right side
    120.30x = 9,349.70
  5. Step 5: Solve for x
    x = 9,349.70/120.30
  6. Step 6: Final answer
    x = 77.72

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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.