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Finding the Fourth Proportional to 800.14, 1,200 and 280.12

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Solution

The fourth proportional to 800.14, 1,200 and 280.12 is: 420.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    800.14 : 1,200 = 280.12 : x
  2. Step 2: Convert to fraction form
    800.14/1,200 = 280.12/x
  3. Step 3: Cross multiply
    800.14x = 1,200 × 280.12
  4. Step 4: Simplify right side
    800.14x = 336,138
  5. Step 5: Solve for x
    x = 336,138/800.14
  6. Step 6: Final answer
    x = 420.10

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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.