Home / 820.20-1,230.45-272.42

Finding the Fourth Proportional to 820.20, 1,230.45 and 272.42

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Solution

The fourth proportional to 820.20, 1,230.45 and 272.42 is: 408.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.20 : 1,230.45 = 272.42 : x
  2. Step 2: Convert to fraction form
    820.20/1,230.45 = 272.42/x
  3. Step 3: Cross multiply
    820.20x = 1,230.45 × 272.42
  4. Step 4: Simplify right side
    820.20x = 335,202.27
  5. Step 5: Solve for x
    x = 335,202.27/820.20
  6. Step 6: Final answer
    x = 408.68

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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.