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Finding the Fourth Proportional to 419.28, 627.90 and 213.54

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Solution

The fourth proportional to 419.28, 627.90 and 213.54 is: 319.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.28 : 627.90 = 213.54 : x
  2. Step 2: Convert to fraction form
    419.28/627.90 = 213.54/x
  3. Step 3: Cross multiply
    419.28x = 627.90 × 213.54
  4. Step 4: Simplify right side
    419.28x = 134,081.77
  5. Step 5: Solve for x
    x = 134,081.77/419.28
  6. Step 6: Final answer
    x = 319.79

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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.