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Finding the Fourth Proportional to 853.90, 1,280.10 and 579.10

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Solution

The fourth proportional to 853.90, 1,280.10 and 579.10 is: 868.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    853.90 : 1,280.10 = 579.10 : x
  2. Step 2: Convert to fraction form
    853.90/1,280.10 = 579.10/x
  3. Step 3: Cross multiply
    853.90x = 1,280.10 × 579.10
  4. Step 4: Simplify right side
    853.90x = 741,305.91
  5. Step 5: Solve for x
    x = 741,305.91/853.90
  6. Step 6: Final answer
    x = 868.14

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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.