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Finding the Fourth Proportional to 821.10, 1,230.90 and 410.02

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Solution

The fourth proportional to 821.10, 1,230.90 and 410.02 is: 614.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    821.10 : 1,230.90 = 410.02 : x
  2. Step 2: Convert to fraction form
    821.10/1,230.90 = 410.02/x
  3. Step 3: Cross multiply
    821.10x = 1,230.90 × 410.02
  4. Step 4: Simplify right side
    821.10x = 504,693.62
  5. Step 5: Solve for x
    x = 504,693.62/821.10
  6. Step 6: Final answer
    x = 614.66

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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.