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Finding the Fourth Proportional to 419.09, 628.17 and 213.45

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Solution

The fourth proportional to 419.09, 628.17 and 213.45 is: 319.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.09 : 628.17 = 213.45 : x
  2. Step 2: Convert to fraction form
    419.09/628.17 = 213.45/x
  3. Step 3: Cross multiply
    419.09x = 628.17 × 213.45
  4. Step 4: Simplify right side
    419.09x = 134,079.73
  5. Step 5: Solve for x
    x = 134,079.73/419.09
  6. Step 6: Final answer
    x = 319.93

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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.