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Finding the Fourth Proportional to 820.29, 1,230.45 and 272.51

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Solution

The fourth proportional to 820.29, 1,230.45 and 272.51 is: 408.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.29 : 1,230.45 = 272.51 : x
  2. Step 2: Convert to fraction form
    820.29/1,230.45 = 272.51/x
  3. Step 3: Cross multiply
    820.29x = 1,230.45 × 272.51
  4. Step 4: Simplify right side
    820.29x = 335,316.21
  5. Step 5: Solve for x
    x = 335,316.21/820.29
  6. Step 6: Final answer
    x = 408.78

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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.