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Finding the Fourth Proportional to 280.29, 419.78 and 270.55

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Solution

The fourth proportional to 280.29, 419.78 and 270.55 is: 405.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.29 : 419.78 = 270.55 : x
  2. Step 2: Convert to fraction form
    280.29/419.78 = 270.55/x
  3. Step 3: Cross multiply
    280.29x = 419.78 × 270.55
  4. Step 4: Simplify right side
    280.29x = 113,571.95
  5. Step 5: Solve for x
    x = 113,571.95/280.29
  6. Step 6: Final answer
    x = 405.20

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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.