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Finding the Fourth Proportional to 1,000.20, 1,380 and 580.32

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Solution

The fourth proportional to 1,000.20, 1,380 and 580.32 is: 800.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,000.20 : 1,380 = 580.32 : x
  2. Step 2: Convert to fraction form
    1,000.20/1,380 = 580.32/x
  3. Step 3: Cross multiply
    1,000.20x = 1,380 × 580.32
  4. Step 4: Simplify right side
    1,000.20x = 800,841.60
  5. Step 5: Solve for x
    x = 800,841.60/1,000.20
  6. Step 6: Final answer
    x = 800.68

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.