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Finding the Fourth Proportional to 419.30, 628.91 and 199.86

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Solution

The fourth proportional to 419.30, 628.91 and 199.86 is: 299.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.30 : 628.91 = 199.86 : x
  2. Step 2: Convert to fraction form
    419.30/628.91 = 199.86/x
  3. Step 3: Cross multiply
    419.30x = 628.91 × 199.86
  4. Step 4: Simplify right side
    419.30x = 125,693.95
  5. Step 5: Solve for x
    x = 125,693.95/419.30
  6. Step 6: Final answer
    x = 299.77

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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.