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Finding the Fourth Proportional to 371.78, 558.38 and 280.65

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Solution

The fourth proportional to 371.78, 558.38 and 280.65 is: 421.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    371.78 : 558.38 = 280.65 : x
  2. Step 2: Convert to fraction form
    371.78/558.38 = 280.65/x
  3. Step 3: Cross multiply
    371.78x = 558.38 × 280.65
  4. Step 4: Simplify right side
    371.78x = 156,709.35
  5. Step 5: Solve for x
    x = 156,709.35/371.78
  6. Step 6: Final answer
    x = 421.51

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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.