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Finding the Fourth Proportional to 419.05, 628.35 and 130.42

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Solution

The fourth proportional to 419.05, 628.35 and 130.42 is: 195.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.05 : 628.35 = 130.42 : x
  2. Step 2: Convert to fraction form
    419.05/628.35 = 130.42/x
  3. Step 3: Cross multiply
    419.05x = 628.35 × 130.42
  4. Step 4: Simplify right side
    419.05x = 81,949.41
  5. Step 5: Solve for x
    x = 81,949.41/419.05
  6. Step 6: Final answer
    x = 195.56

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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.