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Finding the Fourth Proportional to 73.20, 109.80 and 19.09

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Solution

The fourth proportional to 73.20, 109.80 and 19.09 is: 28.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    73.20 : 109.80 = 19.09 : x
  2. Step 2: Convert to fraction form
    73.20/109.80 = 19.09/x
  3. Step 3: Cross multiply
    73.20x = 109.80 × 19.09
  4. Step 4: Simplify right side
    73.20x = 2,096.15
  5. Step 5: Solve for x
    x = 2,096.15/73.20
  6. Step 6: Final answer
    x = 28.64

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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.