Home / 800.20-1,200.44-280.16

Finding the Fourth Proportional to 800.20, 1,200.44 and 280.16

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Solution

The fourth proportional to 800.20, 1,200.44 and 280.16 is: 420.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    800.20 : 1,200.44 = 280.16 : x
  2. Step 2: Convert to fraction form
    800.20/1,200.44 = 280.16/x
  3. Step 3: Cross multiply
    800.20x = 1,200.44 × 280.16
  4. Step 4: Simplify right side
    800.20x = 336,315.27
  5. Step 5: Solve for x
    x = 336,315.27/800.20
  6. Step 6: Final answer
    x = 420.29

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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.