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Finding the Fourth Proportional to 800.18, 1,200.45 and 280.19

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Solution

The fourth proportional to 800.18, 1,200.45 and 280.19 is: 420.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    800.18 : 1,200.45 = 280.19 : x
  2. Step 2: Convert to fraction form
    800.18/1,200.45 = 280.19/x
  3. Step 3: Cross multiply
    800.18x = 1,200.45 × 280.19
  4. Step 4: Simplify right side
    800.18x = 336,358.14
  5. Step 5: Solve for x
    x = 336,358.14/800.18
  6. Step 6: Final answer
    x = 420.35

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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.