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Finding the Fourth Proportional to 800.02, 1,200.20 and 280.10

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Solution

The fourth proportional to 800.02, 1,200.20 and 280.10 is: 420.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    800.02 : 1,200.20 = 280.10 : x
  2. Step 2: Convert to fraction form
    800.02/1,200.20 = 280.10/x
  3. Step 3: Cross multiply
    800.02x = 1,200.20 × 280.10
  4. Step 4: Simplify right side
    800.02x = 336,176.02
  5. Step 5: Solve for x
    x = 336,176.02/800.02
  6. Step 6: Final answer
    x = 420.21

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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.