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Finding the Fourth Proportional to 800.50, 1,200.88 and 280.64

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Solution

The fourth proportional to 800.50, 1,200.88 and 280.64 is: 421.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    800.50 : 1,200.88 = 280.64 : x
  2. Step 2: Convert to fraction form
    800.50/1,200.88 = 280.64/x
  3. Step 3: Cross multiply
    800.50x = 1,200.88 × 280.64
  4. Step 4: Simplify right side
    800.50x = 337,014.96
  5. Step 5: Solve for x
    x = 337,014.96/800.50
  6. Step 6: Final answer
    x = 421.01

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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.