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Finding the Fourth Proportional to 800, 1,200.12 and 280.14

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Solution

The fourth proportional to 800, 1,200.12 and 280.14 is: 420.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    800 : 1,200.12 = 280.14 : x
  2. Step 2: Convert to fraction form
    800/1,200.12 = 280.14/x
  3. Step 3: Cross multiply
    800x = 1,200.12 × 280.14
  4. Step 4: Simplify right side
    800x = 336,201.62
  5. Step 5: Solve for x
    x = 336,201.62/800
  6. Step 6: Final answer
    x = 420.25

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1.5x scale

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.